The official Adobe documentation page for using iOS Universal Links in Adobe AIR is broken -- presumably a change in website formatting has removed critical implementation info.
There are no "steps" to follow, no code snippets detailing what to put in your application descriptor, and no sample apple-app-site-association JSON file.
Q) With the official site broken, where can I find this documentation?
Note: contrast to the Android App Links documentation, which has all relevant code snippets.
I've recovered the page via the web.archive.org backup -- but that's relatively slow. So I've reproduced this missing content below. The Apple Universal Links doc is also helpful defining the specifications for your apple-app-site-association JSON file, and this medium article is a nice overview of the Universal Links in general.
Introduction
With iOS 9, Apple introduced a deep linking feature known as Universal Links. If your application supports Universal Links, iOS 9 users can be redirected to your application just by tapping a link to your website. Universal Links let you replace custom URL schemes with standard HTTP or HTTPS links.
Previously, in order to launch an application through browser, we used custom URL schemes. With iOS 9, there are some restrictions to custom URL schemes. For example:
For an application XYZ to be able to launch an application ABC, you need to add LSApplicationQueriesSchemes to the info.plist of ABC specifying the URL schemes of XYZ and any other applications that you would like ABC to to open.
Alternatively with iOS9, you can use the Universal Links feature to accomplish this task. Universal Links work for all users, if the users have your app installed; the link takes them directly into your app. If they don’t have your app installed, the link opens your website in Safari.
How AIR supports Universal Links
To create an AIR application with Universal Links, you need to follow the below steps:
1) Application Descriptor file
Add the entitlements in your app.xml file as shown below.
<iPhone>
<Entitlements>
<![CDATA[
<key>com.apple.developer.associated-domains</key>
<array>
<string>applinks:www.exampledomain.com</string>
</array>
]]>
</Entitlements>
</iPhone>
Points to note:
Associated domains should be enabled in your provisioning profile for Universal Links to work.
www.exampledomain.com should be replaced with your website address.
2) apple-app-site-association JSON file
When the users install your app, iOS checks this file on your web server to make sure that your website allows your app to open URLs on its behalf. Only you can create and upload this file, so the association of your website with your app is secure.
Create a JSON format file with the content as shown below.
{
"applinks": {
"apps": [],
"details": {
"LKRHPA3TAK.com.exampledomain.app": {
"paths":[ "*" ]
}
}
}
}
Points to note:
The apps key in an apple-app-site-association file is required and should be an empty array.
The value of the details key is an array of dictionaries; one dictionary per application that your website supports. The order of the dictionaries in the array determines the order that the system follows when looking for a match.
Each application-specific dictionary contains an appID (here, it is LKRHPA3TAK.com.exampledomain.app) and a paths key.
The value of the appID key is the application’s team ID (here, it is LKRHPA3TAK) and the bundle ID (here, it is com.exampledomain.app).
The value of the paths key is an array of strings that specify the paths of your website that are supported by the application.
The website paths specified here are case-sensitive.
The JSON file should not be added to the file name (simply keep it as apple-app-site-association).
The JSON file should be signed using the openssl command and certificate from iOS trusted authority. See Shared Web Credentials Reference for details.
This file should be uploaded to the root of your HTTPS web server.
To invoke your application through the browser, you need to enter the Universal Link of your application in the browser. The same can be received in your ActionScript code by registering for NativeApplication invokeEvent. For example:
NativeApplication.nativeApplication.addEventListener(InvokeEvent.INVOKE, invokeHandler)
References
Release Notes | Flash Player® 19 AIR® 19
Apple Documentation
Support Universal Links
Adopting Handoff
Shared Web Credentials Reference
Launch Services Keys
Known Issue
[4042131] An extra InvokeEvent is received with arguments array as null.
Trying to implement universal links in my iOS app running iOS 10, whenever a click a link in my webpage I get the following message in the device log:
Feb 24 15:07:11 iPhone swcd(CoreUtils)[10142] <Notice>: Get info for service 'applinks', app ID '<<NULL>>', domain 'www.redacted...'
My app is setup with the required entitlements and capabilities for this domain. My associated domains entitlements key contains these domains:
applinks:redacted.com
applinks:www.redacted.com
The server is hosting the apple-app-site-association file on the root folder over https. I made sure the content-type of the file is set to application/json and there are no redirects leading to it. The contents of this file are:
{
"applinks": {
"apps": [],
"details": [
{
"appID": "teamid.redacted-app-id",
"paths": ["*"]
}
]
}
}
The way I'm testing this is by going into my site and tapping the first link I find, every time I tap this link I get the message I pasted above and the link opens in safari.
Your description of the problem does not provide any smoking gun indicator of what the issue might be. As I indicated in my previous comment, to really work through Universal Linking issues it is best to know everything that was configured and have a proper test plan that allows the configuration and the testing to be reproduced. There are just too many areas that could be causing problems.
Generally, issues with Universal Linking fall into being either setup issues or testing issues:
Setup Issues
Is the AASA file properly named and properly signed, is it being served from the correct location, are all entitlements correct?
Are the device and provisioning certificates all error-free?
Are you testing with a link that the app has been properly configured to support?
Testing Issues
Are you testing with a physical device? (some say Universal Links now work consistently in the simulator with iOS 10, but I'd still use a physical device)
What links are you testing? You indicate that you are "going into my site and tapping the first link I find." Are these links you are finding in the "redacted.com" domain? I would not use "www.redacted.com" as "www" gets special treatment by many systems and may not work as anticipated.
Could the AASA file have failed to update when the app was first installed/launched due to an issue with the testing environment's network connectivity? I find that the AASA will fail to download if Charles Proxy is capturing traffic, for example. If the AASA file does not make it to the device, Universal Linking will not work.
When testing, it sounds like you are not first pasting the link into Notes and then long-pressing on it. I would strongly recommend that you always test in this fashion first, so as to rule out the issue being related to your website, the application from which you are tapping the link, or the manner in which you are deploying the link (Universal Links will not behave as expected if you paste them into the Safari address bar, for example). When you do test by long-pressing on a link in Notes you should see "Open in App" menu option. If you do see this, but tapping on the link does not open the app, this would indicate that Universal Linking has been disabled on the device.
What is the behavior you are expecting to see when you tap on these links, and what is the actual behavior you are seeing? I often encounter people who believe Universal Linking is broken because they are testing a scenario that Universal Linking does not support. Are you sure the behavior that you are testing for is supported?
Are you using a device and an iOS version that supports Universal Links? Testing should be performed on physical devices, as mentioned earlier, and on iOS versions after 9.0 (where Universal Linking was introduced).
When Universal Linking does not work, there are a lot of things to check. I recommend running through Alex Austen's super blog post on this topic, as doing so may help you spot the problem (here: https://blog.branch.io/how-to-setup-universal-links-to-deep-link-on-apple-ios-9/).
Branch also has a number of tools/resources for identifying Universal Linking issues. They are specifically intended for use with Branch links, but you may still find them helpful:
AASA Validator: https://branch.io/resources/aasa-validator/
Universal Link Validator: https://dev.branch.io/getting-started/universal-linking-validator/guide/
Universal Linking Troubleshooting Guide: https://support.branch.io/support/solutions/articles/6000153326-ios-universal-links-troubleshooting-guide
Look at the logs here is how (taken from SO):
Xcode –> Windows –> Devices & Simulators
Click on device in the left
pane Click Open Console
From there, filter on "swcd" (SharedWebCredential Daemon). Keeping this console open.
You might need to open the console before installing your app dunno if it saves history while closed.
My problem:
I had my apple-app-site-association file hosted on subdomain.mydomain.com but then in Xcode I had Associated Domains set to applinks:*.mydomain.com. In the console mentioned above I saw that in this case the app was trying to get its apple-app-site-association file from mydomain.com. So I changed the Associated Domains to applinks:subdomain.mydomain.com
If none of the above workarounds work for you, please check if you have added activitycontinuation in associated domains or not.
Below is the picture showing the exact place where you have to add that.
(of course you haven't done that already).
I'm trying to make Universal Links work in my app as a replacement of URL Schemes, because since iOS 9 it looks like the system is displaying an alert dialog everytime an app is invoked from Safari. I was hoping that replacing the URL scheme call for a registered URL path in Associated Domains while using Universal Links was going make the dialog disappear.
So instead of calling myscheme://app?params=values I would call https://example.com/universal-link/wakeup?params=values.
My apple-app-site-association (unsigned) file looks like this
{
"applinks": {
"apps": [],
"details": [
{
"appID": "XXXXXXXX.com.company.appid",
"paths": [ "/universal-link/*" ]
}
]
}
}
Please note that, for now, I am using a webserver hosted in the company's LAN, it is not a public server on the Internet. So in the app capability "Associated Domains" I wrote something like applinks:host.company.lan:7700, yet the apple-app-site-association file is never fetched after the app first starts.
I don't know what else to try, so I am considering the server being in a private network might be an issue.
I've found this question in the Apple developer forum that sheds some light on this.
Looks like the issue is, the apple-app-site-association hosted by a domain signed by an untrusted root, and doesn't matter if you install your root certificate in the system, it won't download either. I assume it must be signed by a CA already included in iOS by default.
I got this to work on a private network, but I had to trust the certificates on the device.
To test on a simulator you can drag the certificates into the simulator, on a device you can mail it to the device or airdrop it to it
I´ve been trying with the Developer mode (Associated Domains switch) and this make work for internal domains inside a VPN, but I think this is not the best solution for non technical users.
The Default option following the Apple´s WWDDC´20 video is to install the Root certificate as trusted in the device. But this is not working, at least for me.
So I followed this tutorial exactly and use the same values as the ones provided:
https://blog.branch.io/how-to-setup-universal-links-to-deep-link-on-apple-ios-9
The Apple Association file is also ready in the link directory:
WEB_PAGE:PORT_NUMBER/apple-app-site-association
Everything seems to be set up on this side.
I've added the entitlements, updated the provisioning profile, and everything's set up.
When I run the app on my device, and open the link http://WEB_PAGE:PORT_NUMBER, this always opens Safari.
I even have breakpoints in the following method:
- (BOOL)application:(UIApplication *)application continueUserActivity:(NSUserActivity *)userActivity restorationHandler:(void(^)(NSArray * __nullable restorableObjects))restorationHandler
But zilch.
Has anyone perfected this? Is there something I'm missing?
There are a few possible issues.
Try pasting your domain into this link validator and make sure there are no issues: https://limitless-sierra-4673.herokuapp.com/ (credit to ShortStuffSushi -- see repo)
iOS logs an error message in the system logs if you don't have TLS set up properly on the domain specified in your entitlements. It's buried in the OS logs, not application logs. The error message will look like Sep 21 14:27:01 Derricks-iPhone swcd[2044] <Notice>: 2015-09-21 02:27:01.878907 PM [SWC] ### Rejecting URL 'https://examplecustomdomain.com/apple-app-site-association' for auth method 'NSURLAuthenticationMethodServerTrust': -6754/0xFFFFE59E kAuthenticationErr. Error message pulled from here, quick (incomplete) instructions on using CloudFlare for TLS here.
In my personal testing, clicking/typing in a link in Safari has never once opened the app directly. Clicking from other apps (iMessage, Mail, Slack, etc.) has worked. Others have reported that clicking links in Google search results have opened the app directly.
Note that if a Universal Link succeeds in opening your app and then you click through to Safari (by tapping your site in the top right corner of the nav bar in app), then iOS stops opening the app when you visit that URL. Then in Safari, you can pull down to reveal a banner at the top of the page with "Open". I wasted a lot of time on this. Note that clicking through to the site => disabling UL seems path specific, based on the paths you specify in the apple-app-site-assocation file. So if you have separate routes, yoursite.com/a/* and yoursite.com/b/*, if you click yoursite.com/a/* and it opens your app directly, you then have the option in the top right corner of the app to click through to yoursite.com/a/*. If you do that, subsequent visits to yoursite.com/a/* will open in browser, not app. However, yoursite.com/b/* should be unaffected and still open your app directly.
Let me know if you discover what the issue is. I'm personally very curious about how Universal Links work and what edge cases exist.
There are a lot of ways this can go wrong. Two points caused me trouble:
In Xcode, when you add the Associated Domains entitlement, each entry needs to start with applinks: and then your domain name. E.g. applinks:www.apple.com.
Though Xcode created an entitlements file for me, it did not include in my build: I had to click that box manually.
And yes, after doing that, it wasn't necessary to sign the apple-app-site-association file: it is just plain text, and it works, as long as it's served over HTTPS. (You'll still need to sign it if you're supporting iOS 8, though.)
To help debugging this issue, search for "swcd" in your device's console output when installing your app to see if registering your universal link worked or failed.
Use an actual device, not the simulator.
Delete the app from you device.
Connect the device to your computer, and view the device's console output in xcode. (window -> devices -> [your device] -> open console). Keep this window open.
Install your app and let it launch.
Filter the console output to "swcd". If it's sucessful you will see something like the folowing screenshot. If it fails you'll see something else. If you don't see anything then you messed something fundamental like adding the Associated Domains entitlement.
There is apparently an error in the documentation for making the association file for Universal Links.
Where it says:
The value of the appID key is the app’s team ID and the bundle ID
it should say
The value of the appID key is the app’s Prefix and the bundle ID
For most apps, it seems that the Team ID and app prefixes are the same, but if your app has been in the store for many years, these values can be different.
To find this value, open the Member Center on https://developer.apple.com and look at "Certificates, Identifiers & Profiles", click "Identifiers", then "App IDs" in the table under "Identifiers". Find your app, and use the Prefix value and Bundle ID there to create your AppID for the association file.
To validate apple-app-site-association on the server side, you can
use Apple's official validator.
https://search.developer.apple.com/appsearch-validation-tool/
St.derrick's Answer is informative.
But to enable universal links again to open in app instead of safari we need to do the following thing.
Long press on Universal link in Mail or iMessage, then you will see options whether to open in safari or in App.
I realized that be problem for me was that links to the root directory a (eg. http://example.com/) did not open my app but if I added a path (eg. http://example.com/mypath) it worked. Adding "/" to the paths list sovled it:
{
"applinks": {
"apps": [],
"details": [
{
"appID": "TEAM_ID.BundleIdentifier",
"paths": [ "*", "/" ]
}
]
}
}
As answered by slutsker in this Apple Developer Forums thread.
For anyone who needs to easily test opening (Universal) Links, you can also open the link in your Simulator from the terminal with this command:
xcrun simctl openurl booted yourapp_or_http://yourlink
for example:
xcrun simctl openurl booted https://www.google.com
Quick steps to check whether you have implemented Universal Link correctly.
Tap and hold on the link that you expect to launch the app. You should see a "Open in [your app name]" in the Context Menu.
Open Notes app, type the link you expect to open the app. Tap Done. The link will turn yellow and tapping on the link should open your app, and not Safari.
If the link http://yourDomain.com is not launching the app, try http://yourDomain.com/yourFolder/
In Safari, If the Context Menu shows "Open in [your app name]" in safari, but tapping the link opens the link in safari itself instead of launching the app,
a. Try pulling down on the safari page that opened when the link was clicked like the way you 'pull to refresh'. A banner should appear that can open your app. Tap the banner to open the app, close the app by pressing home button, get back to safari and try launching the app by tapping the link again. This time on, the app should get launched because tapping the banner should have saved the preference to open the link in app.
b. If the app still don't get launched after the step a., try mailing the link to a webmail such as gmail and open the webmail site in safari and try clicking the link. If this works, you may have been trying to launch the app from the same domain as the link. From what I have seen, launching the app from the same domain mostly fails. Probably safari wont care to check whether the destination url is a universal link, when the link is into the same domain that user is on. So try to launch the app from another domain.
It's also super important to increment the project version or build number after integrating universal links. Even if you delete/reinstall, iOS won't pickup the links unless you bump the version.
Universal Links will not work if you paste the link into the browser URL field.
Universal Links work with a user driven <a href="..."> element click across domains. Example: if there is a Universal Link on google.com pointing to bnc.lt, it will open the app.
Universal Links will not work with a user driven <a href="..."> element click on the same domain. Example: if there is a Universal Link on google.com pointing to a different Universal Link on google.com, it will not open the app.
Universal Links cannot be triggered via Javascript (in window.onload or via a .click() call on an <a> element), unless it is part of a user action.
source: https://dev.branch.io/getting-started/universal-app-links/support/ios/#appsbrowsers-that-support-universal-links
The 3rd bullet cost me about a day to figure out.
Incase people here are looking for other solutions, we put together a whole step-by-step on debugging Universal Links as we've seen a lot of issues pop up, causing a LOT of headaches.
Check it out:
Universal Links Debugging Guide
If you're just looking to set up Universal Links fresh, this guide is really helpful:
iOS Deep Linking Setup Guide
Hope they're helpful!
Just thought I would add some things I discovered in case more people encounter the same issues as me in the future. These are mostly related to authentication errors.
Even though apple doesn't explicitly state it, the apple-app-site-association file must be served over https, even if signed. The certificate used for https must also be trusted by apple. So while a certificate added to the device in Settings -> General -> Profiles will allow https in safari, it will not allow universal links to work.
In the device logs, on an authentication error between the device and the server, there will be a value printed like "TrustResultValue" : 4. A TrustResultValue of 5 means the certificate is for the wrong domain (Eg. test.com served from www.test.com). A TrustResultValue of 4 means the certificate is not trusted for this use.
There may be some helpful steps for debugging here. The "Testing access to apple-app-site-association" section is a step by step guide for how to make sure the device is getting the apple-app-site-association file. The steps boil down to:
Uninstall the app. This is necessary because the file is downloaded on install.
Stop the server from properly serving apple-app-site-association.
In xcode, open Window -> Devices and then select your device.
Open the device logs by clicking the triangle at the bottom of the window.
Clear the logs by clicking the trashcan to clear any previous logs that might be related.
Reinstall the app with xcode by clicking the play button.
After the app has launched, if the device is correctly requesting the file then the device logs should contain an error that can be found by searching for "apple-app-site-association".
If the apple-app-site-association file is properly served (step 2 is left out) then there should be no error. An authentication error may instead be displayed if that is the problem.
We've added apple-app-site-association file to this location:
https://example.com/apple-app-site-association
On iOS 9 it worked fine, but on iOS 10 it didn't work.
It appeared that problem was with .well-known path:
https://example.com/.well-known/apple-app-site-association
Because of https://example.com/.well-known/apple-app-site-association path redirected to https://example.com
<Notice>: Allowing redirect 'https://example.com/.well-known/apple-app-site-association' -> 'https://example.com/'
<Notice>: ### Rejecting AASA file size 154466 for URL https://example.com/.well-known/apple-app-site-association
In my opinion if somehow .well-known path doesn't work correctly it breaks universal links.
The most common cause is when user tap on the top right, thus telling iOS to NOT open the app (in this case Uber) in the future.
To fix, pull down to reveal the smart banner and tap on OPEN:
This will subsequently "remember" to open the app.
For ios13, there is a new format - check out here https://developer.apple.com/documentation/safariservices/supporting_associated_domains_in_your_app?language=objc
I updated my file to look like this:
{
"applinks": {
"apps": [],
"details": [
{
"appIDs": ["1234.app.company.appname"],
"appID": "1234.app.company.appname",
"components": [
{
"/": "/login"
}
],
"paths": [ "/login" ]
}
]
},
"webcredentials": {
"apps": ["1234.app.company.appname"]
}
}
After spending a day trying to get this to work, Restarting my phone solved the problem.
Uninstalling/Reinstalling the app didn't work either.
I've managed to make it work, but it took quite some time and struggle. Note that unless you sign the apple-app-site-association file (signing is optional!) tapping on a link in Safari will not open your app (it has caused me a lot of headache).
Sometimes I find that everything is fine with the association file but iOS decides to always open the universal link in Safari. To test if the app recognises the app link I add the URL to Notes or a Calendar entry and then long press it so the contextual menu appears. If it says "Open in {YOUR APP}" then the link is working but iOS is deciding to open it in Safari. Tapping "Open in {YOUR APP}" will tell iOS to open valid universal links via your app from then on.
Took me close to a day to figure this out.
The issue I had was not downloading the updated provisioning profiles in XCode (I also restarted XCode after this).
(Preferences > Accounts > View Details > Download All)
You can test universal links in simulator
From the App Search Programming Guide: Support Universal Links
After two days it turned out for me, that these kind of links (from branch)
applinks:xxxx.app.link
work only after Archiving (also Ad-hoc) the application and install it to the phone.
Hope this helps someone because this took me about two days to figure out.
We had to add www. to our associated-domains in our .entitlements file.
<string>applinks:www.yourdomain.com</string>
<string>activitycontinuation:www.yourdomain.com</string>
Because if we used yourdomain.com instead of www.yourdomain.com our servers did a redirect -> 304 and then didn't include the content-type: application/json for the apple-app-site-association file.
N.B. the universal links still work for yourdomain.com and www.yourdomain.com
If you are hosting your apple-app-site-association on Firebase, make sure to put it in /.well-known/ subdirectory! It appears that Xcode queries that URL first, and if it succeeds, it makes no attempt to query the apple-app-site-association in the root directory. For some reason, firebase engineers made the hosted websites to automatically respond to /.well-known/apple-app-site-association with an empty (but correctly formed) association file that overrides your custom one, leaving you with no clue why nothing works!
Go to developer.apple.com and edit one of your distribution profiles. In the editing page you can open a pop up for App IDs that will show a list of your app names and in () round brackets behind the app's name it reveals all your real App IDs. Some apps might have your team ID as prefix but some do not. Make sure to use exactly what you see in that pop up menu inside the () and put it into the apple-app-site-association details appID field. I had exactly this issue with an app and its universal links.
The issue for me turned out to be the apple-app-site-association file. According to Apple's documentation, only the applinks parameter is required. I added the activitycontinuation parameter and it worked.
{
"activitycontinuation": {
"apps": [
"9JA89QQLNQ.com.apple.wwdc"
]
},
"applinks": {
"apps": [],
"details": [{
"appID": "9JA89QQLNQ.com.apple.wwdc",
"paths": [ "/wwdc/news/", "/videos/wwdc/2015/*" ]
}]
}
}
Haven't really seen the exact same issue/solution combo that got it working for me so might as well add mine incase someone has the same problem!
For my app I am using a custom URL scheme (set in APP_TARGET > Info > URL Types) and set the URL scheme from here into the Firebase console to match but still wasn't working.
My problem was actually two problems:
Watch out if checking Automatically Manage Signing
If you are checking Xcode's "Automatically manage signing" setting like I was, since I was just trying to make a quick demo app, you will want to ensure that the TeamID that is used matches the one in your Firebase console. I originally went to my Apple Developer Account and copied the team ID from my Membership page, but later saw that the actual ID being used by Xcode was different. (You can find this in APP_TARGET > General > Signing > Signing Certificate. For me it looked like iPhone Developer: My Name (TEAM_ID)).
Prefix your TeamID to your Bundle Identifier in your URL Types
After I ensured these matched in my Firebase console and Xcode, my next problem was the identifier for my URL scheme. It's typical to use your bundle identifier here, but Firebase actually prefixes this with the Team ID you gave in your Firebase console, so I had to prefix it to the identifier in the URL types section in Xcode as well.
After these two fixes and re-downloading the GoogleService-Info.plist file I had no problem open up my dynamic links.
After two days of total desperation, I think I've finally fixed it. Here is my solution:
It seems that older apps use a different app prefix than newer apps. Newer apps only use the Team ID for this purpose. If the app prefix and the team ID are not identical, it seems that you need to specify the activity continuation field in the apple app site association file:
{
"activitycontinuation": {
"apps": [
"YOUR_APP_PREFIX.de.company.app"
]
},
"applinks": {
"apps": [],
"details": [
{
"appID": "YOUR_APP_PREFIX.de.company.app",
"paths": ["/*"]
}
]
}
}
Another thing I experienced during my hell ride was that deleting the app and restarting the device seems to be the only way to force refresh this file.
For me, after implementing all the answers from above and testing that the AASA file was indeed being downloaded with mpoisot's answer, my issue was that in Xcode I added the associated domain as:
applinks:example.com
and in my notes app I was trying to use:
Https://example.com
because my AASA is not signed and I wanted to ensure I was serving it through HTTPS. So it worked when in my notes app I tried to use:
example.com
It works for me on a physical device, using iOS 12.1.2 with either a development build from Xcode or a distribution build from Testflight
In my case I needed to make the server serve the apple-app-site-association file using content type: application/pkcs7-mime. In nginx I did it using this approach:
location ~ /.well-known/apple-app-site-association {
default_type application/pkcs7-mime;
}
As other suggested I also had to make sure I:
Use the new iOS apple-app-site-association format https://developer.apple.com/documentation/safariservices/supporting_associated_domains
Use the correct TEAM ID so it becomes "appIDs": [ "TEAM_ID.my-app-bundle-id"],
Make sure in Xcode's entitlements, the app associations start with applinks:
Note that I never saw the "success" messages in the Console app as shown in screenshots by another user. In the console I kept getting Entry [...] needs its JSON updated because the app PI changed, but this was not an issue.
Also note that when trying to open the apple-app-site-association in the browser, the file gets downloaded instead of displayed, but this was not an issue in my case.
And as always, use a real device, re-install app whenever you change things, potentially also restart device and maybe increment app version number.