Using the accelerometer of an iOS device in background [duplicate] - ios

This question already has answers here:
Receive accelerometer updates in background using CoreMotion framework
(2 answers)
Closed 7 years ago.
I have an iPad that stays on my table at home all day while I'm at work. With my kids around (who are prohibited from using it), I was wondering if I could design an app (or download it, but I did not find it) that would alert me if the device moves.
For example, if one of my kids pick it up, it would detect it through the accelerometer and send me an email.
Is that possible to do with the application not running, but just installed? Like if it was running in the background. I know it is possible with the GPS, but I'd like to do it with the accelerometer to make it detect small movements.
Thank you for your help

Your problem has been issued in several threads all over stackoverflow.
Next time you should really use the search function or at least post some code.
In the meantime check this:
From this thread Receive accelerometer updates in background:
You can not only use accelerometer for fatching data from background,
And as you say your App registers for location updates , start
location manager in forground.
Implementing Long-Running Background Tasks For tasks that require more
execution time to implement, you must request specific permissions to
run them in the background without their being suspended. In iOS, only
specific app types are allowed to run in the background:
Apps that play audible content to the user while in the background,
such as a music player app Apps that record audio content while in the
background. Apps that keep users informed of their location at all
times, such as a navigation app Apps that support Voice over Internet
Protocol (VoIP) Apps that need to download and process new content
regularly Apps that receive regular updates from external accessories
Short Version: It is not possible to ONLY get acceleration data in background.

Related

Swift background work

I'm new to iOS development and I'm using Swift in my current project.
I'm trying to achieve something similar I did in Android. I'm trying to run a background service when the app is closed/minimised that will get executed every 2 seconds to keep the user informed that the app is still running in the background and checking for status with the server.
How can I achieve that? I've tried using the "background fetch" method but it doesn't get executed every 2 seconds.
The background service will run no longer than 5 minutes if it matters.
No you can't do that. What you can do is, call a service in applicationDidEnterBackground that lets your server know that your app is in background or killed(You will get very less time for this to get executed, approx. 3-5 sec.).
An Android app like the one you described will likely drain the device’s battery prematurely. This is the simple reason why Apple has restricted background execution to a clearly defined set of tasks:
Apps that play audible content to the user while in the background, such as a music player app
Apps that record audio content while in the background
Apps that keep users informed of their location at all times, such as a navigation app
Apps that support Voice over Internet Protocol (VoIP)
Apps that need to download and process new content regularly
Apps that receive regular updates from external accessories
This list is taken from Apple’s official description of background tasks: Background Execution.

Keep an iOS application running in background forever

This question might be duplicate of many others but I am still asking because I really need to get any solution of it.
For iOS versions prior to 6, for devices other than those having an A7 chip.
I have an application which interacts with the Accelerometer. I am also running it in background by playing a sound file and turning the Audio services ON for background task.
Now If any third application plays music, it takes control of shared Audio Session of device which causes my background thread to call completion handler assuming that background task has been completed.
Now my application is interruptible by iOS and iOS can kill it if it remains in background for a long time after which I couldn't interact with accelerometer.
Is there any way/trick/hack to keep my application running all the time until unless I kill it by my own.
Again, this is a duplicate question but I really wanted to share my problem with you people to help me in this sense.
Apple is very clear on this:
Implementing Long-Running Background Tasks
For tasks that require more execution time to implement, you must
request specific permissions to run them in the background without
their being suspended. In iOS, only specific app types are allowed to
run in the background:
Apps that play audible content to the user while in the background,
such as a music player app
Apps that record audio content while in the background.
Apps that keep users informed of their location at all times, such as
a navigation app
Apps that support Voice over Internet Protocol (VoIP)
Apps that need to download and process new content regularly
Apps that receive regular updates from external accessories
Collecting accelerometer data is not listed. Therefore, what you are trying to do is not possible. "Ways, tricks, hacks" tend to get discovered quickly and offending apps removed from the App Store.

Launch my app from bluetooth iBeacon connection (Private API)

I am creating a private distribution app and I am wondering if it is possible, using any methods or private API's, to open my app when a bluetooth connection has been made.
What I have discovered so far is that with iOS 7 and the ability to use iBeacons you can enter into bluetooth proximity and you can have your app send a notification to allow the user to then open the app.
What I am hoping to do then is have the app running in the background and listen for an iBeacon connection and, if one has been made, actually launch the app without the users control instead of just sending a notification.
I realize this would never be allowed publically, however is there anything private I can look at to achieve this without jailbreaking? I know to launch some apps you can do [[UIApplication sharedApplication] openURL:[NSURL URLWithString:url]]; however I want my app to listen for an iBeacon and then open itself up.
Is there any way or work around to achieve this?
Moving app from background to foreground without user interaction is pain in the ass. Sorry, don't have a solution, just want to share some information:
I asked the same question here and posted a bounty on it and got no good response:
Show some UI from background in audio player or VOIP app on iOS
At some moment I found a solution with the help of another person. It was based on usage of GSEvent (sending clicks to UI). You can look following questions. However, as I know, in iOS 7 these API became protected by entitlement. So, this method is dead (most likely).
Using GraphicsServices.h/GSEvent as well as compiling CLI iPhone tools with Xcode
Use GSEvent to send touch event,but it's invalid.
Simulating System Wide Touch Events on iOS
iPhone, how to fire a button event in programmatically
Apps can use region monitoring to be notified when the user crosses geographic boundaries or when the user enters or exits the vicinity of a beacon. While a beacon is in range of the user’s device, apps can also monitor for the relative distance to the beacon.
In iOS, regions associated with your app are tracked at all times, including when your app is not running. If a region boundary is crossed while an app is not running, that app is relaunched into the background to handle the event. Similarly, if the app is suspended when the event occurs, it is woken up and given a short amount of time (around 10 seconds) to handle the event. When necessary, an app can request more background execution time.
For detailed info:
https://developer.apple.com/library/ios/documentation/UserExperience/Conceptual/LocationAwarenessPG/RegionMonitoring/RegionMonitoring.html#//apple_ref/doc/uid/TP40009497-CH9-SW1
There are two scenarios: you either want users to be able to do something with your device other then use your app, or you want them to always be locked into your app.
In the former case you should trust user. Just show the push, timer or location notification and let them decide to launch the app or not.
In the latter case just lock the device using guided access mode.

Collecting accelerometer data in background

I am developing an iOS 4 + application, which can transmit accelerometry data collected on an iPhone to a server. The app should collect data even when the application enters in background (I want to know the person’s movements).
After doing some research on the Internet, I learned that the app is killed 10 minutes after being closed, and it is not possible to implement it the same way as on Android (using services).
Only some tasks can run in background like an audio player, VOIP or geolocation.
I read somewhere on the Internet that we can use workarounds for letting the application running in background. It uses the audio player, which plays a mute sound. However, this workaround seems not to be accepted by Apple.
Do you see any solution to my problem?
If you register your app to listen to location, and use CoreMotion, you can get accelerometer data in background.
This is duplicate with: How Nike+ GPS on iPhone receives accelerometer updates in the background?
From iOS 9.0 we got CMSensorRecorder that can record accelerometer data at 50Hz even if app is killed.
More info as usual in Apple documentation.
CMSensor documentation
The accellerometer is not available for background threads. Read this MacWorld article on what is possible and what not.

Running IOS App with Screen Locked

I am working on a sports app that uses GPS and OpenEars text-to-speech. The app delivers speed and other GPS info to the user audibly (via earphones) so the user (skier, cyclist, etc) can get the GPS info without looking at the screen. In order to save battery life, I would like the app to run in the background with the screen off. Is this possible with IOS? I tried setting "Required backgrund modes" for both GPS and audio, but my app quits working when the screen is off.
thanks..
One one to get around it is to have a silent audio file playing, when there is no audio, it might get your app rejected in the app store though... here is a question that talks about the silent audio file playing to keep in the background... It might get through app store approval in your situation since it is an app that relays on audio as one of its main functionalities..
You can subscribe to GPS info change notifications and your app will run when something needs to be updated. Check this.
Please note this sentence:
"If you leave this service running and your application is subsequently suspended or terminated, the service automatically wakes up your application when new location data arrives. At wake-up time, your application is put into the background and given a small amount of time to process the location data. Because your application is in the background, it should do minimal work and avoid any tasks (such as querying the network) that might prevent it from returning before the allocated time expires. If it does not, your application may be terminated."
There's no way to do it as service except some special cases provided by ios. But you can simulate it. This post answer how to:
https://stackoverflow.com/a/19121250/2835520
I hope it's gonna help!

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