This might be asking for the moon but here goes...
Is it possible to have an iOS app receive data and then forward it all while running in the background?
We're a restaurant currently using an ordering system that uses a main iPad as the till, with a second iPad in the kitchen to receive orders, and another third iPad used by the servers to take orders. Orders are sent to the main till which relays orders to the kitchen.
Works great... Unless someone switches app on the main till iPad to our other (necessary) hosting app, then all hell breaks loose and all orders stop getting sent.
Developer (small team) has told us it's impossible to solve but I have done some digging into recent Apple APIs that allow simple tasks to run in the background and have seen a few promising options, or perhaps it's possible via the External Accessory Framework, or even syncing via iCloud? A question for the more knowledgable than me, but is there currently a workaround to solve this that I could suggest or are they right in that it's currently impossible in iOS?
Yes there are ways to have an app in the background receive data, generally using either:
beginBackgroundTaskWithName:expirationHandler:
or
beginBackgroundTaskWithExpirationHandler:
Take a look at the Background Execution section in the documentation for more info...
Related
I was wondering how social networking apps, such as Twitter, Facebook and WhatsApp update their user interface in real-time when another user interacts with the user of the app. To use the best example I can think of: when you have a chat window open in WhatsApp, the UI updates automatically (without any user actions required) when the user you're chatting with interacts with you. Messages appear on your screen without refreshing and the "last seen" status at the top of the screen updates automatically when your chat partner either goes offline or comes back online. I can think of two ways to achieve this:
Remote push notifications: this approach strikes me as the 'cleanest' way to do this, but it's probably also the riskiest way. Using silent notifications (content-available) to pass data to another device at the moment a user does something, would probably save you a lot of HTTP requests and therefore would make your app consume a lot less data and CPU usage. The risk of this approach is that a user can easily disable ALL push notifications to save battery power (including silent notifications) and then your app wouldn't be able to get notified on events remotely.
Local UI refreshing: This approach is obviously the safest, but I think it's really 'nasty' and eventually everyone would feel the downside of it. Constantly refreshing the UI and re-retrieving data from the database to make sure the latest messages and statuses are displayed to the user would be safe in the way that your app doesn't have to rely on the device's battery and background mode settings, but the downside is that this will make your app consume a lot of data and battery power, which would be bad for the user's data plan and his device. I also don't think Apple would approve of an app that's consuming so much data and power.
I've just implemented a chat function into my own app, and I want to enable the same real-time UI updating that WhatsApp uses. What would be the best way to do this? Should I use one of the two methods above or can someone think of another way to do this? By the way, I'm a relatively new programmer who just recently learned how to develop iOS apps (Swift). I'm very far from being a pro, so please go easy on the explanations and work method capabilities. Thanks!
The chat apps make use of WebSockets to create a constant connection with the client and a backend server.
This article on Appcoda can help you start learning about Socket.io. It answers your questions and also helps you to create a demo app.
I was trying to get a specific info before a IOS App development task which I searched but couldn't find anything relevant.
Wanted to know whether this requirement restricts (non compliance issue as per publish guidelines) the app to be published in App Store with features as below
User scans and lists all available wifi connections in a tableview
Selects one of the Wifi connection and connects on button click
Stores the password and SSID for future connections.
Would there be any compliance issue related to the same functionalities when submitting to IOS app store. One of my colleague have advised me about the same but not able to explain why? Which I tried to find out searching the internet, but too specific to find anything relevant. Deeply appreciate an Expert advise on this.
Thanks in advance.
I can't find anything in the Review Guidelines that would object your app idea: https://developer.apple.com/app-store/review/guidelines
A couple of areas where you should have a more detailed look:
2.5.1 Apps may only use public APIs.
2.5.9 Apps that alter the functions of standard switches, such as the Volume Up/Down and Ring/Silent switches, or other native user
interface elements or behaviors will be rejected.
5.1 Privacy
Technically, I'm not sure if it's even possible to change the WIFI not via the settings app, so I'd have a look their first. (https://apple.stackexchange.com/questions/1592/is-there-an-ipod-app-to-easily-switch-wifi-on-and-off)
I don't believe I've ever seen an app or a way to change SSID outside the Settings app. I explored a way to detect network changes, connects, disconnects, which work fine while the app is running. I was never able to influence how the user connected, just that a change happened. It also falls apart pretty quickly when the user backgrounds the app. Trying to keep a background task open long enough to poll the current connection fails pretty fast.
I wish Apple would provide some system level notification of Wifi connect events. This could be very useful to developers that want a little more control than Background App Refresh events.
I've been using this app called Moment that tracks how much time I spend on my device every day. I think it's very cool, and at the same time am very curious how it works. I don't have tons of mobile development experience, as I've mainly built web apps, but I'm curious how this kind of functionality could be achieved.
I did a few quick Google searches and found that iOS does have some support for background task execution. The functionality lies in four categories:
Play audio
Receive location updates
Perform finite-length tasks
Background fetch
It looks like I can't do anything tricky using audio callbacks, as Apple will reject the app, but I'm wondering if I can do something with (3).
They do it using Custom Profiles.
I work as a software developer, but I am absolutely new to Apple in general. We have the following case in a project, and we have not been able to figure out a solution for it, I would really appreciate some advise to find a solution (or drop the case if not possible)
A (potential) customer with multiple retail stores is interested in having a very simple app to display some content (this could an image or html, nothing too complicated) and periodically update this content from a server (this requirement is important). So it is very simple case, to use the device screen as advertising space
But here is the catch, users should be able to go out of this app and check out the device's system and other apps, and then the content should come back on the foreground when the device is idle. So basically we need something like a screensaver app that fetches the content (images) from a server and keeps them updated.
We have been looking at the guided access mode, but we are not sure it fulfills the requirements, because of the following issues
- Allowing the user to check out the device system and other apps. As far as we understood guided access restricts the device to one app.
- Re-launch the app (or bring it to the foreground) when the device has been idle for a period of time.
Note that we should account for a variety of devices (iPhone and iPads) with different OS versions
I appreciate your help and ideas. Thanks.
Apple does not allow apps to run continuously in the background except for a small limited group of exceptions. (music playing apps, for example.)
It's possible to set up your app to pretend to be a music playing app, and stay running in the background, but that means you will not be allowed on the app store.
Your client may be able to use the enterprise program to create apps for use in their retail stores. Enterprise apps don't have to go through the app store approval process.
I did this for a client recently (for an enterprise app.) As I recall I would have the app request background processing as soon as it moved to the background, and when it was notified that it's background time was ending, I would play a short "silence" sound and request another block of background time. Unfortunately it was work for hire and the contract ended, so I did not retain the source code.
I have a rather odd question. I am writing a turn based iOS game and was wondering if there is a way to store data in your application that can be accessed even when the app is closed. I have a handful of NSStrings that I would like GameCenter to be able to swoop by and scoop up even if the app is closed on the user's device. Is this possible? I know it won't work while the device is off, but it would be nice if they don't have to have my app open for it to collect their turn.
Any background processes have about 30 seconds to complete once your app is put in the background except for specific processes like playing music etc, so basically no not really. You can see the docs here:
Multitasking docs