How to disable Crashlytics for iOS during development?

If you use Swift, this woud work:

#if !DEBUG
    Fabric.with([Crashlytics.self])
#endif

Development builds are also DEBUG builds, You are probably meaning Ad-Hoc builds. Since the release and Ad-Hoc build use the same configuration you will not be able to tell them apart.

You bets option is to create a new configuration for the AppStore. For this configuration add a Preprocessor Macro, Like FABRIC=1

Then in you build code:

#ifdef FABRIC
    [Fabric with:@[CrashlyticsKit]];
#endif

To disable firebase crashlytics for debug mode in swift:

    #if DEBUG
        Crashlytics.crashlytics().setCrashlyticsCollectionEnabled(false)
    #endif

I think you can try this :

#ifndef DEBUG
 [Fabric with:@[CrashlyticsKit]];
#endif