I have an app that uses iBeacons and allows location monitoring when the app is in the background. When the app is first placed into the background, monitoring works correctly (I get didEnterRegion and didExitRegion callbacks as the user moves around). It seems that this continues to work correctly for some time.
However, after some time (e.g., the next morning), the app seems to stop receiving location updates. I have locationManager.pausesLocationUpdatesAutomatically set to false. Is anything else I need to do to allow long running monitoring updates in the background?
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I'm trying to call didEnterRegion and didExitRegion for geofencing events when the app is killed (double tap home and swipe up by the user), but I'm not sure if this is even possible. From what I've seen, such as here, it isn't possible. However, I was wondering if something had changed in iOS 11, or if there was another way to do this?
After running many tests, I can confirm that Geofence Events are called, even when the app is terminated (swipe up). However, the user must have authorized location to be used when the app isn't running, and other background location functions, such as didUpdateLocation will not be called.
I make iBeacon-based application. I want to reach better proximity than gives major-minor, I want to use ranging. Problem, that it doesn't work more then 10 seconds in background. Ok, I use startUpdatingLocation and ranging works fine ... until device is rebooted. After reboot, ranging doesn't work. I think it because of startUpdatingLocation doesn't perform in background and after rebooting application doesn't become foreground. Have anybody solve the same problem, how to start ranging after rebooting device?
Only monitoring can launch an app into the background based on a beacon detection. To do what you want, you have to both monitor for beacons and range for beacons at the same time. The monitoring didEnterRegion callback will trigger a background launch of your app, and then ranging will start automatically if you have it set up.
locationManager.startMontoringForRegion(beaconRegion)
locationManager.startRangingBeaconsInRegion(beaconRegion)
You can also extend ranging beyond 10 seconds for up to 3 minutes, as described in my blog post here.
I am developing an iOS app to monitor iBeacons. It works well in both foreground and background. I also need it to keep monitoring even when the screen is off. Now my problem is, when I turn off the screen with the shoulder button, NSLog shows that the iBeacon signal goes off (RSSI=0, beacon.accuracy=-1.0) accordingly, and 10 seconds later, there is no beacon found at all, while the delegate method locationManager:didRangeBeacons:inRegion: is called continuously. It seems that the app is running when the screen is off but iOS turns off the location service for iBeacon ranging. I tried to set "locationManager.pausesLocationUpdatesAutomatically = NO;" but still doesn't work. Is there any advice on this issue? Thanks in advance.
It seems that you're doing ranging instead of monitoring. Ranging only works when the app is active—either in the foreground or in the background. The catch is, iOS will automatically put an app to sleep a few seconds after you navigate away from it, or lock the screen.
What you have to keep in mind is, there's really no such thing as "permanent background state" on iOS. Apps run in the background for some limited time while transitioning to the suspended state (to let them, e.g., finish uploads/downloads), and there are also Background Modes that sometimes enable an app to run in the background, but these are usually reserved for very specific apps—e.g., the "audio" Background Mode means an app can be running in the background as long as it plays music, etc. There is a Background Mode for "location" services, but it's reserved for turn-by-turn navigation apps.
Beacon monitoring however continues running even if your app goes to sleep, or gets terminated by the iOS due to memory pressure. When you go in or out of range of a beacon, iOS will launch your app into the background to handle the event, giving it a few seconds (which you can extend up to a few minutes with a Background Execution Task) to do so (you can range during that time), but then it's back to sleep.
You might also want to take a look at this question:
Receive signal from beacon while app is in the background
I am working on an app that records journeys by tracking the GPS. Everything is working fine in background if we start the process from the foreground (by tapping the button "Start Journey").
Now the idea is start record these journeys automatically triggered by a iBeacon. When the iPhone gets inside of a beacon region, the app is detecting this and calls the function LocationManager.StartUpdatingLocation();
PROBLEM:
Using iBeacons from background, we only get 10 seconds ranging and that is the same figure I have got to get location updates from GPS.
All I need is detect I am inside of beacon region, start GPS and keep it running, and only disable the GPS when I am outside of the region.
Unfortunately, you can use CoreLocation geofences in the background, but you can't get fine GPS updates continually. This isn't a Xamarin thing -- it is an iOS restriction.
I wrote the blog post that #RobertN referenced about extending background beacon ranging to 3 minutes. But I don't think this is much help to you because you want to do get GPS updates continually, which Apple simply does not allow.
We actually recently wanted to implement this behavior in one of our apps too, and found that if we start significant location updates (startMonitoringSignificantLocationChanges) in the foreground, then we're able to start regular location updates (startUpdatingLocation) in the background, in our didEnterRegion implementation.
(Naturally, your app needs the "always" authorization to access Location Services, and the "Location updates" Background Mode enabled.)
Our app is still pending review, so whether that's a bug or a feature of Core Location, and whether Apple is okay with that, remains to be seen.
The best explanation to this I seen can extend that 10 seconds to 3 minutes, but that is it... App rejection is an issue with continuous background operation unless your app truly is reviewed as a Navigation app:
A second approach involves tracking the beacon in the background,
noting its estimated distance, and only triggering an action when the
beacon is estimated to be within a specific range. This approach is
problematic on iOS, because CoreLocation generally allows only 10
seconds of ranging time when an app is in the background. If a beacon
is first detected at 50 meters, and a person is approaching the beacon
at one meter per second, the mobile device will still be 40 meters
away when iOS suspends the app and stops it from ranging.
The good news is that it is possible to extend background ranging time
on iOS. If your app is a navigation app, you can specify location
updates in the “Required background modes” in your Info.plist. But
this approach makes it harder to get AppStore approval -- you have to
convince reviewers that your app is providing navigation services to
the user. This probably isn’t true for many apps that simply want to
use beacons to trigger at a specific distance.
Fortunately, you can still extend background ranging time without
requesting special background modes. The time you can get is limited
-- only three minutes. But this clock restarts each time your app is woken up in the background, meaning you can get an extra three minutes
of ranging time each time your app detects a beacon (enters a beacon
region) or stops seeing beacons (exits a beacon region.)
Via: http://developer.radiusnetworks.com/2014/11/13/extending-background-ranging-on-ios.html
I want to implement long-running background timer which sends user's location to server periodically.
To do this, I set location mode for UIBackgroundModes, and call beginBackgroundTaskWithExpirationHandler when the application goes to background.
And for CLLocationManager, I use startUpdatingLocation method (don't want to use significant change, because I need high precision location).
But around 26minutes after the app goes to background, it stops to send location to the server. But the app isn't crashed, so after I bring the app to foreground, it can resume its timer.
26minutes is from experiments, with iOS 6.1, iPhone 5.
Here are some questions,
I can't understand why it suspends after 26mins not 10mins, which is known as time limit for background task.
Before 16mins, backgroundTimeRemaining methods returns double max value. But after 16mins, it decreases from 600, so it suspends the background task after 10mins.
I already tried to call beginBackgroundTaskWithExpirationHandler inside of expiration handler, but no use.
If there's anyone who has a clue for this problem, will be greatly appreciated.
https://github.com/voyage11/Location
Use this code.you can set time interval you want to call it. I have tried many codes, but i found this as most accurate and least battery issue.This is also awesome for background location service. :)
if you have set UIBackgroundModes successfully，the App can run a long time in the background while you are moving. But, if you stop moving for over 10 minutes（maybe more）， the App will be suspended by the system. Your App will be awake if the location updates，but this awake time will be very short，so you must cal
beginBackgroundTaskWithExpirationHandler method to handle location update.