I faced this problem after building an app in XCode. Here are some logs:
2019-12-23 11:43:38.538929+0200 signer[87746:1862730] You've implemented -[<UIApplicationDelegate> application:performFetchWithCompletionHandler:], but you still need to add "fetch" to the list of your supported UIBackgroundModes in your Info.plist.
2019-12-23 11:43:38.541152+0200 signer[87746:1862730] You've implemented -[<UIApplicationDelegate> application:didReceiveRemoteNotification:fetchCompletionHandler:], but you still need to add "remote-notification" to the list of your supported UIBackgroundModes in your Info.plist.
2019-12-23 11:43:38.546 [info][tid:main][RCTCxxBridge.mm:213] Initializing <RCTCxxBridge: 0x7fa7de405980> (parent: <RCTBridge: 0x600002424cb0>, executor: (null))
2019-12-23 11:43:38.550376+0200 signer[87746:1862730] Initializing <RCTCxxBridge: 0x7fa7de405980> (parent: <RCTBridge: 0x600002424cb0>, executor: (null))
2019-12-23 11:43:38.639 [info][tid:main][RCTRootView.m:293] Running application signer ({
initialProps = {
};
rootTag = 1;
})
2019-12-23 11:43:38.639089+0200 signer[87746:1862730] Running application signer ({
initialProps = {
};
rootTag = 1;
})
2019-12-23 11:43:38.990604+0200 signer[87746:1862730] -[RCTReconnectingWebSocket initWithURL:queue:]: unrecognized selector sent to instance 0x600000149650
2019-12-23 11:43:39.046365+0200 signer[87746:1862730] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[RCTReconnectingWebSocket initWithURL:queue:]: unrecognized selector sent to instance 0x600000149650'
*** First throw call stack:
(
0 CoreFoundation 0x00007fff23c7127e exceptionPreprocess + 350
1 libobjc.A.dylib 0x00007fff513fbb20 objc_exception_throw + 48
2 CoreFoundation 0x00007fff23c91fd4 -[NSObject(NSObject) doesNotRecognizeSelector:] + 132
3 CoreFoundation 0x00007fff23c75c4c ___forwarding___ + 1436
4 CoreFoundation 0x00007fff23c77f78 _CF_forwarding_prep_0 + 120
5 signer 0x00000001083876a5 _ZL17socketForLocationP8NSString + 821
6 signer 0x000000010838708c -[RCTPackagerConnection init] + 284
7 signer 0x0000000108386f44 __49+[RCTPackagerConnection sharedPackagerConnection]_block_invoke + 36
8 libdispatch.dylib 0x0000000109240d48 _dispatch_client_callout + 8
9 libdispatch.dylib 0x0000000109242297 _dispatch_once_callout + 66
10 signer 0x0000000108386ef4 +[RCTPackagerConnection sharedPackagerConnection] + 84
11 signer 0x000000010830e757 -[RCTDevSettings setBridge:] + 567
12 Foundation 0x00007fff25712ee3 -[NSObject(NSKeyValueCoding) setValue:forKey:] + 325
13 signer 0x0000000108373f2d -[RCTModuleData setBridgeForInstance] + 509
14 signer 0x0000000108373ab3 -[RCTModuleData setUpInstanceAndBridge] + 2131
15 signer 0x0000000108375427 __25-[RCTModuleData instance]_block_invoke + 39
16 signer 0x0000000108396083 RCTUnsafeExecuteOnMainQueueSync + 67
17 signer 0x0000000108375122 -[RCTModuleData instance] + 738
18 signer 0x00000001082b32d4 __49-[RCTCxxBridge _prepareModulesWithDispatchGroup:]_block_invoke + 196
19 libdispatch.dylib 0x000000010923fdd4 _dispatch_call_block_and_release + 12
20 libdispatch.dylib 0x0000000109240d48 _dispatch_client_callout + 8
21 libdispatch.dylib 0x000000010924eadb _dispatch_main_queue_callback_4CF + 721
22 CoreFoundation 0x00007fff23bd4049 __CFRUNLOOP_IS_SERVICING_THE_MAIN_DISPATCH_QUEUE + 9
23 CoreFoundation 0x00007fff23bceca9 __CFRunLoopRun + 2329
24 CoreFoundation 0x00007fff23bce066 CFRunLoopRunSpecific + 438
25 GraphicsServices 0x00007fff384c0bb0 GSEventRunModal + 65
26 UIKitCore 0x00007fff48092d4d UIApplicationMain + 1621
27 signer 0x00000001081dc8d0 main + 112
28 libdyld.dylib 0x00007fff5227ec25 start + 1
)
libc++abi.dylib: terminating with uncaught exception of type NSException
(lldb)
Same project builds fine on android, but ios throws this error. I have not found anything on the web to solve this type of problem. Any help appreciated!