I'm facing the same issue on IOS 15. And I found that --- SIGPIPE Crash, if your project contains Socket , #import <UIKit/UIKit.h> #import "AppDelegate.h" //#import "MatrixHandler.h" #import <signal.h> int main(int argc, char * argv[]) {     NSString * appDelegateClassName;     @autoreleasepool {         struct sigaction sa;         sa.sa_handler = SIG_IGN;         sigaction(SIGPIPE, &sa, 0);         // Setup code that might create autoreleased objects goes here.         appDelegateClassName = NSStringFromClass([AppDelegate class]);     }     return UIApplicationMain(argc, argv, nil, appDelegateClassName); }