App crashes and restarts phone - ios

I'm beta testing an app, and on most devices it works fine. But I found at least one device (iphone 6s, but I have other of that working fine), it's not the app that crashes, the whole telephone just restarts.
Nothing to find in the logs and no clue where in the app this is caused.
How is this even possible?
Where to start looking?

I encountered a similar problem, an app crash that totally reboot my iPhone. I discovered what was with this workaround:
Connect your device to your Mac
Open Xcode --> Window --> Devices
Select on the left your device
Clean on the bottom the log
Redo the same steps for crash the app
See what happens on the log
For more clarity, you should have this window:
You probably see a lot of lines but with a little patience you should see what it's the problem, or just see the area problem at least.
I hope this helps!

So in the end it was a kind of memory problem. But not because waisting the whole system memory.
It was a simple recursion. In some cases it missed the breaking condition. Did not consume noticeable cpu or much RAM, but a very fast stack overflow.

Related

iPhone restarts after API call

I am facing a very weird issue: my iPhone is restarting.
This issue occurs in a particular scenario only.
Step 1: I have a sync process in which I'm loading data for the whole app. So I'm basically doing a heavy API call by uploading 4-5 camera captured images and syncing the app data;
Step 2: After syncing, I'm pressing the iPhone home button to make the app go in background;
Step 3: I'm locking the iPhone screen(by using side button);
After a few seconds I'm seeing the apple logo and the phone seems to restart. This is not replicating when the app is connected in debug mode. I checked the debug navigator app is using only 125 MB of memory, disk and network values is 0%. Energy Impact is showing high, I'm not sure this is due to high energy impact. I'm facing this issue only on iOS 12.4.
The fact that the phone (or possibly just springboard) restarts, and not just your application means this is Apple's bug. You're not supposed to be able to crash iOS even if you try.
Finding a likely cause will be hard since the system is not behaving the way it's supposed to. The device's logs may have more information from things other than your app. This may be a system API breaking due to any number of actions from your application.
Often with this kind of thing the next OS version will fix it, but if that's not the case or it's important to track down I would try removing ways you're interaction with the system (background APIs, notifications, etc.) and see if anything fixes the issue.
If you find the problem, you may even be doing things the "correct" way according to the documentation and have to find a workaround. If you have the time you can submit a bug to Apple so the underlying issue has a better chance of being fixed.
It seems when your app is in the background and phone locked, Automatic Reference Counting (ARC) closes some connection or deallocates a resource that makes the iPhone restart. Are you closing all connections and removing all references once the upload is complete?
Phones do not spontaneously restart just because of an app’s actions. You’re having an issue with your phone, not with a program. You need to repair or replace the phone.

My iOS app every now and then refuses to launch until I reinstall it

I've got an app that uses Core Data that sporadically stops launching so I have to reinstall it using XCode and then it launches again like normal for a while, with all the Core Data information still preserved.
I have seen that an app often stops launching when the target of an app is too low in comparison to the device software version, however this is not so for this app and device (iPhone 6s).
Have you had such an issue before? What do you think could be causing this problem?
There are many, many, many things that could cause an app to fail to launch. You need to narrow things down and collect some data so that you can find out what the problem is and do something about it. Right now you don't even know that it's related to Core Data, you're just guessing.
For a crash on launch, look at the device console and see what messages appear when you try to launch the app and it fails. You can get the device console messages by
Connecting your device to your Mac
Opening Xcode's "Devices" window (cmd-shift-2)
Looking in the bottom half of the window
A better way to watch the console is to use the free iOS Console app.
The problem was that, as mentioned by dan in the comments, the code was being signed for a short period of time (7 days) and so I had to keep re-installing it on the iOS device to keep it working. Thus to keep the app working indefinitely a paid developer account is needed.
Also mentioned in this reddit forum:
https://www.reddit.com/r/jailbreak/comments/4hotx3/news_free_developer_account_installs_reduced_to_7/

User suddenly can't get past launch image screen

A user has reported that my app suddenly won't launch on their device. They sent me a video, and they launch the app, the launch image screen shows for a split second, but then crashes back to the iOS home screen.
The user tried deleting and reinstalling the app with no benefit.
I use Crashlytics, and am not getting any reports of crashes from them (or any other user- although I've seen them in prior versions so I know it's working correctly). I'm also not seeing any crashes in iTunes connect.
I asked the user to send me any crash reports in the Settings Diagnostics section and they said there are none listed for my app.
I have confirmed that their iOS version is supported by my app. (iOS 8.4).
I'm not sure where to go next, and would appreciate any pointers. Sorry for the vague question but I have posted everything that I know about the situation.
Just wanted to provide some closure on this. The user ended up wiping and restoring their device, and it solved the problem. It seems extreme to me but it was their own suggestion and didn't take them long to do. So I'm not sure what caused this but that's one (albeit brute force) way to fix it.

Xcode 5.1 very slow to build and run on iPad Air

While using Xcode 5.1 to deploy our iOS application I am seeing quickly build and say "Running on iPad Name" but it doesn't launch the application for a little over 7 minutes. When I tap on the status bar at the top for more information it says "SandboxingApplication."
This does not happen on other iPads that we use with the same application.
Any ideas? I've tried all the basics like restarting the device, Xcode, and my computer.
You already said it:
This does not happen on other iPads that we use with the same
application.
That's the point, you'll have to reinstall the iPad. Some time ago I had a iPhone 3GS for testing on which it sometimes also took minutes to launch the app. Xcode behaved like what you described, showing "Running on DeviceName".
But although this iPhone is older it hadn't been always this slow. After I restored it from iTunes it again was pretty much faster.
Finally with the help of #flowmachine1 this is solved! It was fixed by:
Deleting Derived Data
Clean Project
Delete App and Reinstall
Thanks so much!
It could be really any issue, but here are some troubleshooting tips.
Restart Xcode and iPad (You already did it)
Try to create a new Project, and try to run it on the iPad Air (Let me know the comments below what happens)
Reinstall Xcode (Most common fix)
Also report to Apple, if none of those fixes work, https://developer.apple.com/bug-reporting/.
Thank you.
I've nailed down one cause, for my situation at least. The app's sandboxed area is huge (gigabytes) as it contains a large amount of resources (as discussed here). Wiping out these resources prevents the delay in the sandboxing process (with the unfortunate side effect of rendering half of the app unusable).
I can only assume that, as part of attaching the debugger, some processing of each file in the sandbox has to occur every time, and it is this process that is taking the time.
The resources are in the application support directory. If anyone knows of a way to mark or relocate these files to improve the speed of the sandboxing process I'd be very interested to hear (and would award the bounty).
Well, I'm running apps on an iPad Air here and it runs in just a few seconds, using Xcode 5.1 and Xcode 6 (beta 4). So, I'd guess three possibilities here:
Your Mac's HDD is failing, or your app is very large (having GiBs of files OR thousands and thousands of small files). You already said your app has 27MB, so size shouldn't be the issue here. Unless you're talking about a 27MB .ipa file, which is compressed. If your IPA contains 27MB, the app itself can be rather big (not enough for 7 minutes sandboxing time, but affects the sandboxing time.)
You're out of RAM memory on your mac, which causes memory swapping. This can easily lead to 7 minutes build time.
Your USB cable (or port) is damaged. I tried using a damaged cable before, and even with the basic templates that Xcode has I would take several minutes to run it on the device.

IPad - Crashing with no apparent reason

I know it's a bit weird but I have no code at all to put here, unless I copy all of it.
My project is crashing with no apparent reason. I've read this solution: iPhone application is crashing and not leaving behind a .crash log file
and I'm using Instrument for searching for leaks and other possibilities for those crashes.
Another strange thing is: even when I run my app with debug on XCode, it just stop to work on my IPad but it looks it is still running.
And the last and more strange thing: there's no crash log at all on my device. Before somebody ask, it is enable to record crash logs.
Does anybody have any idea for helping me?
Regards
I've had this happen to me before on various platforms. If its crashing on you, whether its an iPhone app, openGL / DirectX program, try these steps:
Have you tried to undo your last change and get to the point where it last worked?
Have you tried placing a print outputs to the terminal to see how far your program is executing? Start at the beginning and work your way into your program. This is especially useful when there is no crash log.
Also in particular to iPhone apps: Have you checked your xib's? Did you recently re-factor and change the name of a class maybe? You might need to re-link your nib to your classes. This on more than one occasion has caused apps of mine to crash with no error. Hope this helps.
I doubt you are still wondering about this, but my answer is that you were experiencing your app getting killed by the OS due to using too much memory. This will silently fail in the log in my experience when running on the device.
You will have to go into the Organizer to the device console and crash reports that get stored on the device to see the clues.
The reason your crash stopped when you got an iPad 2 is because the iPad 2 has twice the memory of the iPad 1 (which is dramatically under-stocked with RAM)

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