I'd like to play a sound periodically while the app is in the background but after doing some research it's not certain if this is possible. Before I give up or waste too much time trying I want to double check with the community if this is really possible or not.
I figured out how to enable playing sounds while the app is in the background but the app is still eventually killed and the timer stops firing (there's a 10 minute period it runs in suspended mode if I use beginBackgroundTask: but that's not enough). Other ideas I had:
1) There appears to be a "background fetch" mode which could maybe be used like a timer but this is a hack and may be rejected by Apple.
2) Loop blank audio in the background or some other looping part of audio API's to keep the app alive? Again Apple may reject that even it's possible.
3) Enable the location API to keep the app alive and play audio. Hack again, bad for battery and Apple 99% will reject this.
4) I read somewhere that push notifications could work for this but that requires a complicated server backend and if it's possible that last resort.
Are any of those methods viable or are there others?
You can use scheduled Local Notifications with sounds.
Related
I'm working on an iOS app that uses MPMusicPlayerController.systemMusicPlayer to play songs from Apple Music to the user.
My app should be able to append songs to the Music player's queue based on messages it receives from a server. I have this working with a simple WebSocket connection between the app and the server, but as soon as the app enters the background the socket is automatically closed (which makes sense).
Because the actual music playback is done by the Music app, I can't use the Background Audio background mode to keep my app alive. Is there a way around this?
Things I have already considered (and why I don't think they will work):
Remote Notifications are throttled too slow to be of any real use
Background App Refresh is also too slow
PushKit / VoIP (the app isn't a VoIP app)
Playing "blank" or nearly silent audio over the actual audio which seems too "hacky" and likely won't pass app review
Using background location tracking (again, almost certainly won't pass review)
Ditching systemMusicPlayer completely and using AVAudioPlayer with the Apple Music API (this would be reinventing the wheel a little bit and would force streaming even if the media was downloaded)
Using applicationQueuePlayer and just forcing the user to stay in app (this would be a bad user experience imo, they should be able to listen in the background)
Any help would be appreciated, thank you!
In iOS 15 and later, you should be able to just set the background plist flag for your app, and then just use ApplicationMusicPlayer.
https://developer.apple.com/documentation/musickit/applicationmusicplayer
A lot of todo-list apps such as Wunderlist offer some kind of reminder feature which usually just fires off a notification.
But I have never encountered an app that offer a similar notification view as the built in preinstalled alarm clock. You know, that locks the phone and offers a snooze option.
This makes me wonder if the alarm clock functionality that is built into the preinstalled iOs app from Apple including setting time or add a snooze button etc is only available for that particular app?
Since I'm a designer without any coding skills I only want to know if it possible or not.
Unfortunately this is unavailable for developers. You can check all of alarm clock apps in AppStore, all of them are using the standard local notifications. Which will fire once and that's all. You can of course set your custom sound and change couple of options, but it will never work like one build in Clock app inside iPhone.
You can read more about local notifications in Apple documentation: https://developer.apple.com/reference/usernotifications/unnotificationrequest
I figured Alarmy is constantly playing (when there is an alarm set up) a silent sound in the background. Like Spotify, but silent. This keeps the app active all the time. I came to this conclusion by logging the result AVAudioSession.sharedInstance().isOtherAudioPlaying (Swift 4) in my own application. Whenever Alarmy is terminated it returns false, whenever Alarmy is running in the background it returns true. Same thing happens for the app linked by Ernesto Elsäßer.
I used the same technique and I also used this pod to trigger a function when the time comes and start the real music.
I did this for testing and am not going to make an app out of it because playing silent sounds in the background is against Apple's rules. I don't know how Alarmy (or other apps that use this same method) got away with it.
Some related questions:
How do you constantly run in background?
App “Alarmy” is able to play iTunes song from background state… How?
Wake up application in background using AudioSession like Alarmy iOS app
Also you can check this article out.
This app seems to do exactly this, but I have no clue how ...
I tested it, and it managed to start playing music on a locked device at an arbitrarily chosen time, and for way longer than the 30s timeframe allowed for notification sounds. Further, the music is streamed from an online radio station, meaning they found a way to ...
wake up the app from a scheduled notification without user interaction
create a socket connection to a radio station in the background
start playing sound in the background for an indefinite amount of time
I also tried out the alarm in Airplane Mode, and it still played a locally stored backup song, so it probably doesn't abuse the VoiP background mode or push notifications, but really is triggered by a local notification ...
So although I can't tell how, it looks like there is an App Store Review-proof way to create a real alarm app.
(I am not affiliated with the developers of this app, just did some research on what's possible.)
I'm writing an exercise app that runs a series of timers back to back that are determined by the users exercises and the times they have entered for them e.g. push UPS for 30 seconds, squats 20 seconds...
When the timer reaches zero, the app speaks the next exercise, and starts the next timer.
The app also allows the user to play music from playlists whilst they exercise, so I have set the Audio background mode in capabilities in swift.
When in the foreground, everything works as expected, and the times, and speech fire when they are meant to, however, when the app is backgrounded, only the music continues and everything else stops.
I understand that Apple have strict rules on background processes and multitasking, but I have downloaded a number of apps that seem to work fine in the background and continue to speak the intervals as they become due (Seconds Pro, Onyx Timer etc.)
I have researched this for days, but cannot come up with an answer, background fetching doesn't seem to be reliable enough for a time based app, as you can't guarantee when it will fire, I've also looked into local notifications, but they don't allow speech when they trigger, just a short sound, they also have a limit of 64 notifications, which limits the amount of intervals the user can set
I have set the app to keep the screen awake whilst the timer screen is running, but this means you have to keep the screen on whilst you train, which in turn will add an unnecessary drain on the battery, which seems to go against everything Apple is trying to accomplish with the limited background activity
Push notifications seemed like one solution, but this would mean I have to setup some sort of external server and surely this would be interrupted if the user didn't have an Internet connection.
I have read multiple threads about people running a silent audio stream in the background to keep their app alive in the background (not approved by Apple), but my app already plays audio in the background and has no effect on the rest of the app being suspended?
How would I go about achieving this?
I have thought of a workaround, but I don't know if it's good practice, or if it will get the app kicked if I try to upload it to the app store
My solution was to queue my speech based on the time set in each timer
for timer in 0...timersArray.count{
let sentence = timer.speech
let speechUtterance = AVSpeechUtterance(string: "\(sentence)")
speechUtterance.postUtteranceDelay = timer.time
synth.speakUtterance(speechUtterance)
}
Then the speech would just trigger at the appropriate times, even though the timer wasn't running in the background
When I ran this code, it worked as expected and the speech triggered when the timer would have finished (just as if it was running)
When running this code though, I noticed that not only did it trigger the speech at the correct time, it also kept my app running in the background, which is exactly what I wanted in the first place.
Is this allowed practice, or will it get booted from the store?
As my app plays music in the background and has the audio capability set, is there a way I can use a similar approach, but with the music in the background, rather than the queued utterance approach.
I tried with MPMediaPlayer, AVPlayer, and AVQueuePlayer, but nothing worked, the music played in the background, but the rest of the app stopped
If I set "Does not run in background" to "Yes" in the Plist.info, the app will now run when the screen is locked, it still won't run in the background though?
There are so many apps in the App Store that seem to run happily in the background, I can't believe it's this hard to get it to work?
A number of the ones I have tried, are not listed under notifications, so I know it's not a local notification, they also work in airplane mode, so it can't be remote push notifications
I created an app that will send text messages through an API similar to Twilio, and I have an NSTimer that fires a function every set amount of time. The problem is that if you press the home button, it will totally stop the timing, which defeats the purpose.
I have read that it is possible to have your phone play a mute sound until closed to make sure it still runs in the background, but I can't find a resource on how to do this. Here is an example: To run NSTimer in background
If anyone has any information on how to do this, I'm sure it is very simple, and I very much appreciate the help.
Thank you.
If you set up your app as a background sound playing app then yes, it is technically possible to play a "silent sound" in order to keep it active in the background, but your app will be rejected by Apple if you do this.
Apple expressly forbids what you are trying to do.
You should look at using scheduled local notifications. Those will alert the user, who can bring your app to the foreground and let it perform the desired task.
So I need this app to run timer for more than 3 minutes, and play a sound like very 45 seconds, most of the solutions here are just for less than 3 minutes on iOS. Is there a way to make it run all the time, unless the app stops?
After the research, I guess the solution is implement beginBackgroundTaskWithExpirationHandler
and stops it by giving a handler and set location update on plist?
As for audio, besides setting the plist, anything else need to do to play audio?
Swift how to use NSTimer background?
iphone - NSTimers in background
Run app for more than 10 minutes in background
No, in order to save all of us from apps that kill our batteries, Apple does not allow apps to continue to run in the background for more than a few minutes. There are only very special limitations (music playing apps, VOIP, navigation apps, etc.) which permit ongoing operation. In terms of details, this is described in About the Background Execution Sequence.
If you want to notify user of something at some future time, you can use local notifications. When you do this, though, you don't control whether your app restarts or not. Only if the user taps on the notification (assuming they even granted your app notification privileges at all), will the app be reopened. For more information, refer the the local notification discussions in UserNotification framework documentation. But note, this is not intended for alerts every 45 seconds, but rather for a significant notification scheduled for some future time.
For discussion of how one might marry local notifications with timers, see swift NSTimer in Background and this follow up question swift calculate time for timers running in background.