Ionic app crash

I developed an Ionic app. It is published in the Google Play store for a while now and works fine. I’m having problems with iOS. At first it crashed by clicking an input or when I reopened the app (from background). I removed a plugin, built an ad hoc package for iOS. I installed the IPA on my iPhone by using iTunes. It worked perfectly: no more crashes by clicking the inputs or reopening the app. I thought the problem was solved and uploaded the app to App Store Connect. This morning the app was visible in the app store, I downloaded it, clicked on a input and it crashed again… Also reopening the app results in a crash …

When I launch the app with xCode, I get an error message on:

int main(int argc, char* argv[])
@autoreleasepool {
int retVal = UIApplicationMain(argc, argv, nil, @“AppDelegate”);
return retVal;

Device log:
Date/Time: 2018-06-12 08:52:51.6956 +0200
Launch Time: 2018-06-12 08:52:35.3658 +0200
OS Version: iPhone OS 11.3.1 (15E302)
Baseband Version: 2.03.12
Report Version: 104

Exception Type: EXC_CRASH (SIGABRT)
Exception Codes: 0x0000000000000000, 0x0000000000000000
Triggered by Thread: 0

Application Specific Information:
abort() called

Filtered syslog:
None found

Last Exception Backtrace:
0 CoreFoundation 0x1842b6d8c __exceptionPreprocess + 228
1 libobjc.A.dylib 0x1834705ec objc_exception_throw + 55
2 CoreFoundation 0x1842c4098 -[NSObject+ 1388696 (NSObject) doesNotRecognizeSelector:] + 139
3 UIKit 0x18e36ade4 -[UIResponder doesNotRecognizeSelector:] + 291
4 CoreFoundation 0x1842bc5c8 forwarding + 1379
5 CoreFoundation 0x1841a241c _CF_forwarding_prep_0 + 91
6 Duofor 0x102c7be88 -[CDVDecimalKeyboard isTextAndDecimal] + 147080 (CDVDecimalKeyboard.m:164)
7 Duofor 0x102c7bc80 -[CDVDecimalKeyboard processKeyboardShownEvent] + 146560 (CDVDecimalKeyboard.m:134)
8 libdispatch.dylib 0x183ba8ae4 _dispatch_client_callout + 15
9 libdispatch.dylib 0x183bb0f18 _dispatch_continuation_pop$VARIANT$mp + 423
10 libdispatch.dylib 0x183bba808 _dispatch_source_invoke$VARIANT$mp + 1363
11 libdispatch.dylib 0x183bb55b8 _dispatch_main_queue_callback_4CF$VARIANT$mp + 715
13 CoreFoundation 0x18425cbc8 __CFRunLoopRun + 2271
14 CoreFoundation 0x18417cda8 CFRunLoopRunSpecific + 551
15 GraphicsServices 0x18615f020 GSEventRunModal + 99
16 UIKit 0x18e15d78c UIApplicationMain + 235
17 Duofor 0x102c5e720 main + 26400 (main.m:32)
18 libdyld.dylib 0x183c0dfc0 start + 3

So, a package build from Ionic (development and production) results in a working iOS app, but when I launch the app with xCode or download it from the app store it results in crashes by clicking an input or reopening the app.

I hope someone can help me out with this.