Call the lowercaseString function of NSString, it crashes, very strange

All are system functions, do you have any ideas to solve the crash?

I have configured two appids in appIDs, but only the first one is valid and the second one is invalid, how can I fix it? for example： "appIDs": [ "ABCDE12345.com.example.app", "ABCDE12345.com.example.app2" ],

I found that this app allows users to log in directly with the last account password. I would like to know what interface is this provided by the system. This is not Apple Login！

I want to judge whether the app is playing audio through the cpu usage of com.apple.coreaudio.AQClient, so whether it can cover the situation of all players?

When backgroundTimeRemaining==0, why does the program continue to run in the background? Running for a long time, more than an hour

When the program is running in the background, will the app be suspended after the avaudioplayer is paused?

When the program is running in the background, will it be suspended when it receives an AVAudioSessionInterruptionNotification notification?

My app has applied for the permission to play audio and video in the background, but I found that it survived for a long time without hanging when the audio and video were not played in the background. I want to locate the cause, is there any good way?

I want to download the organizer data and upload it to my own platform. Is there any relevant data interface?

I receive thousands of metrickit crash reports every day ： EXC_CRASH:<RBSTerminateContext| domain:10 code:0x8BADF00D explanation:process-launch watchdog transgression: application:6559 exhausted real (wall clock) time allowance of 60.00 seconds call stack： 0 libobjc.A.dylib libobjc.A.dylib 1 libobjc.A.dylib libobjc.A.dylib 2 libobjc.A.dylib libobjc.A.dylib 3 libobjc.A.dylib libobjc.A.dylib 4 dyld dyld 5 dyld dyld 6 dyld dyld 7 dyld dyld I have a few questions: 1.Does this mean that the dynamic link is stuck? 2.Where should I fix this problem?

Is there a way for iOS NSURLSession to control dns resolution by itself, similar to the ability of the libcurl library (https://curl.se/libcurl/c/CURLOPT_RESOLVE.html). Because I found that my app's domain name was hijacked in the public network.

Directly set the mapping relationship between domain name and IP, let my app use it with NSURLSession, Is there a related interface?

I used the app this morning, uninstalled and reinstalled this afternoon. Will the data reported by MetricKit the next day include the data before uninstalling and reinstalling the previous day?

If the app is pre-warm and started, the memory resource is limit and the app exits in background. Does it count as a backgroundExitData.cumulativeMemoryResourceLimitExitCount in Metric Kit?