We have exactly the same story with our Xamarin iOS app. It started to crash on iOS15 Beta5. The reason for a crash has not been identified yet. You can deobfuscate your stack trace by following these steps: Get the first number from the crash file in the Binary Images section: in your case (0x102560000) Go to directory that contains *.dSYM in out case it is bin/iPhone/release/ And run in terminal atos -arch arm64 -o YourAppName.app/YourAppName -l 0x102560000 0x1035088e8 or copy all addresses into stack.txt file and run atos -arch arm64 -o YourAppName.app/YourAppName -l 0x102560000 -f stack.txt Out stack trace: wrapper_managed_to_native_Foundation_NSObject_xamarin_set_gchandle_with_flags_safe_intptr_intptr_Foundation_NSObject_XamarinGCHandleFlags (in {AppName}) + 136 Foundation_NSObject_CreateManagedRef_bool (in {AppName}) (NSObject2.cs:286) Foundation_NSObject_InitializeObject_bool (in {AppName}) (NSObject2.cs:273) Foundation_NSObject__ctor_Foundation_NSObjectFlag (in {AppName}) (NSObject2.cs:148) UIKit_UIApplicationDelegate__ctor (in {AppName}) (UIApplicationDelegate.g.cs:883) MvvmCross_Platforms_Ios_Core_MvxApplicationDelegate__ctor (in {AppName}) (MvxApplicationDelegate.cs:22) MvvmCross_Platforms_Ios_Core_MvxApplicationDelegate_2_TMvxIosSetup_REF_TApplication_REF__ctor (in {AppName}) + 20 {AppName}_AppDelegate__ctor (in {AppName}) (/<unknown>:1) wrapper_runtime_invoke_object_runtime_invoke_dynamic_intptr_intptr_intptr_intptr (in {AppName}) + 272 mono_jit_runtime_invoke (in {AppName}) (mini-runtime.c:3171) mono_runtime_invoke_checked (in {AppName}) (object.c:3220) mono_runtime_invoke (in {AppName}) (object.c:3107) native_to_managed_trampoline_1(objc_object, objc_selector, _MonoMethod*, bool, unsigned int) (in {AppName}) (registrar.m:32) -[AppDelegate init] (in {AppName}) (registrar.m:9828) 0x000000018370b498 wrapper_managed_to_native_UIKit_UIApplication_UIApplicationMain_int_string___intptr_intptr (in {AppName}) + 344 UIKit_UIApplication_Main_string___intptr_intptr (in {AppName}) (UIApplication.cs:86) UIKit_UIApplication_Main_string___string_string (in {AppName}) (UIApplication.cs:66) {AppName}_Application_Main_string__ (in {AppName}) (/<unknown>:1) wrapper_runtime_invoke_object_runtime_invoke_dynamic_intptr_intptr_intptr_intptr (in {AppName}) + 272 mono_jit_runtime_invoke (in {AppName}) (mini-runtime.c:3171) mono_runtime_invoke_checked (in {AppName}) (object.c:3220) mono_runtime_exec_main_checked (in {AppName}) (object.c:5284) mono_jit_exec (in {AppName}) (driver.c:1328) xamarin_main (in {AppName}) (monotouch-main.m:0) main (in {AppName}) (main.m:184)