swift - App crashing only on Device -

this strange crash happens running on devices, while in simulator works normally. debugging line line, noticed occurs while append string value array of doubles. convert double using extension:

extension string { func todouble() -> double? {     return nsnumberformatter().numberfromstring(self)?.doublevalue     } } 

so crashing line is:

litros.append(temp_litros.todouble()!) //litros array , temp_litros string 

the error:

fatal error: unexpectedly found nil while unwrapping optional value 

i don't understand why works in simulator , doesn't on devices.

anyone have ideia happening here? in advance!

crash report:

incident identifier: 49f378a2-e7d9-4985-b208-99f529ae8813 crashreporter key:   fe58b29412047d4d8980b9cb66ae017f1c2db7d5 hardware model:      iphone7,2 process:             nuvem [9479] path:                /private/var/mobile/containers/bundle/application/8989627a-4064-428c-888b-c09f00a3ea0b/nuvem.app/nuvem identifier:          br.com.gimenez.nuvem version:             1 (1.0) code type:           arm-64 (native) parent process:      launchd [1]  date/time:           2015-07-23 18:07:12.529 -0300 launch time:         2015-07-23 18:07:05.037 -0300 os version:          ios 8.4 (12h143) report version:      105  exception type:  exc_breakpoint (sigtrap) exception codes: 0x0000000000000001, 0x0000000100659474 triggered thread:  0  thread 0 name:  dispatch queue: com.apple.main-thread thread 0 crashed: 0   libswiftcore.dylib              0x0000000100659474 0x100598000 + 791668 1   nuvem                           0x00000001000b5110 nuvem.graficoviewcontroller.viewdidload (nuvem.graficoviewcontroller)() -> () (graficoviewcontroller.swift:69) 2   nuvem                           0x00000001000b5410 @objc nuvem.graficoviewcontroller.viewdidload (nuvem.graficoviewcontroller)() -> () (graficoviewcontroller.swift:0) 3   uikit                           0x0000000188d14c14 -[uiviewcontroller loadviewifrequired] + 688 4   uikit                           0x0000000188d14924 -[uiviewcontroller view] + 28 5   uikit                           0x0000000188eb71ec -[uinavigationcontroller _startcustomtransition:] + 708 6   uikit                           0x0000000188dc9e80 -[uinavigationcontroller _startdeferredtransitionifneeded:] + 464 7   uikit                           0x0000000188dc9c4c -[uinavigationcontroller __viewwilllayoutsubviews] + 52 8   uikit                           0x0000000188dc9bcc -[uilayoutcontainerview layoutsubviews] + 196 9   uikit                           0x0000000188d116f0 -[uiview(calayerdelegate) layoutsublayersoflayer:] + 576 10  quartzcore                      0x000000018864ddb4 -[calayer layoutsublayers] + 148 11  quartzcore                      0x000000018864881c ca::layer::layout_if_needed(ca::transaction*) + 316 12  quartzcore                      0x00000001886486c0 ca::layer::layout_and_display_if_needed(ca::transaction*) + 28 13  quartzcore                      0x0000000188647e54 ca::context::commit_transaction(ca::transaction*) + 272 14  quartzcore                      0x0000000188647bd4 ca::transaction::commit() + 524 15  quartzcore                      0x00000001886412fc ca::transaction::observer_callback(__cfrunloopobserver*, unsigned long, void*) + 76 16  corefoundation                  0x00000001842542a0 __cfrunloop_is_calling_out_to_an_observer_callback_function__ + 28 17  corefoundation                  0x000000018425122c __cfrunloopdoobservers + 356 18  corefoundation                  0x000000018425160c __cfrunlooprun + 832 19  corefoundation                  0x000000018417d2d0 cfrunlooprunspecific + 392 20  graphicsservices                0x000000018dbd36f8 gseventrunmodal + 164 21  uikit                           0x0000000188d7af3c uiapplicationmain + 1484 22  nuvem                           0x00000001000ad9b8 main (appdelegate.swift:14) 23  libdyld.dylib                   0x0000000196612a04 start + 0  thread 1 name:  dispatch queue: com.apple.libdispatch-manager thread 1: 0   libsystem_kernel.dylib          0x0000000196710c24 kevent64 + 8 1   libdispatch.dylib               0x00000001965f5e6c _dispatch_mgr_invoke + 272 2   libdispatch.dylib               0x00000001965e7998 _dispatch_mgr_thread + 48  thread 2: 0   libsystem_kernel.dylib          0x000000019672bc78 __workq_kernreturn + 8 1   libsystem_pthread.dylib         0x00000001967c52d8 _pthread_wqthread + 988 2   libsystem_pthread.dylib         0x00000001967c4eec start_wqthread + 0  thread 3: 0   libsystem_kernel.dylib          0x000000019672bc78 __workq_kernreturn + 8 1   libsystem_pthread.dylib         0x00000001967c52d8 _pthread_wqthread + 988 2   libsystem_pthread.dylib         0x00000001967c4eec start_wqthread + 0  thread 4: 0   libsystem_kernel.dylib          0x000000019672bc78 __workq_kernreturn + 8 1   libsystem_pthread.dylib         0x00000001967c52d8 _pthread_wqthread + 988 2   libsystem_pthread.dylib         0x00000001967c4eec start_wqthread + 0  thread 5: 0   libsystem_kernel.dylib          0x000000019672bc78 __workq_kernreturn + 8 1   libsystem_pthread.dylib         0x00000001967c52d8 _pthread_wqthread + 988 2   libsystem_pthread.dylib         0x00000001967c4eec start_wqthread + 0  thread 6 name:  com.apple.nsurlconnectionloader thread 6: 0   libsystem_kernel.dylib          0x0000000196710e0c mach_msg_trap + 8 1   libsystem_kernel.dylib          0x0000000196710c84 mach_msg + 68 2   corefoundation                  0x0000000184253720 __cfrunloopservicemachport + 196 3   corefoundation                  0x0000000184251674 __cfrunlooprun + 936 4   corefoundation                  0x000000018417d2d0 cfrunlooprunspecific + 392 5   cfnetwork                       0x0000000183c5a590 +[nsurlconnection(loader) _resourceloadloop:] + 436 6   foundation                      0x000000018519ddb4 __nsthread__main__ + 1068 7   libsystem_pthread.dylib         0x00000001967c7dc4 _pthread_body + 160 8   libsystem_pthread.dylib         0x00000001967c7d20 _pthread_start + 156 9   libsystem_pthread.dylib         0x00000001967c4ef4 thread_start + 0  thread 7 name:  com.apple.cfsocket.private thread 7: 0   libsystem_kernel.dylib          0x000000019672b498 __select + 8 1   corefoundation                  0x0000000184259124 __cfsocketmanager + 668 2   libsystem_pthread.dylib         0x00000001967c7dc4 _pthread_body + 160 3   libsystem_pthread.dylib         0x00000001967c7d20 _pthread_start + 156 4   libsystem_pthread.dylib         0x00000001967c4ef4 thread_start + 0  thread 8: 0   libsystem_kernel.dylib          0x000000019672bc78 __workq_kernreturn + 8 1   libsystem_pthread.dylib         0x00000001967c52d8 _pthread_wqthread + 988 2   libsystem_pthread.dylib         0x00000001967c4eec start_wqthread + 0  thread 9: 0   libsystem_kernel.dylib          0x000000019672bc78 __workq_kernreturn + 8 1   libsystem_pthread.dylib         0x00000001967c52d8 _pthread_wqthread + 988 2   libsystem_pthread.dylib         0x00000001967c4eec start_wqthread + 0  thread 10: 0   libsystem_kernel.dylib          0x000000019672bc78 __workq_kernreturn + 8 1   libsystem_pthread.dylib         0x00000001967c52d8 _pthread_wqthread + 988 2   libsystem_pthread.dylib         0x00000001967c4eec start_wqthread + 0  thread 11: 0   libsystem_kernel.dylib          0x000000019672bc78 __workq_kernreturn + 8 1   libsystem_pthread.dylib         0x00000001967c52d8 _pthread_wqthread + 988 2   libsystem_pthread.dylib         0x00000001967c4eec start_wqthread + 0  thread 12: 0   libsystem_kernel.dylib          0x0000000196710e0c mach_msg_trap + 8 1   libsystem_kernel.dylib          0x0000000196710c84 mach_msg + 68 2   corefoundation                  0x0000000184253720 __cfrunloopservicemachport + 196 3   corefoundation                  0x0000000184251674 __cfrunlooprun + 936 4   corefoundation                  0x000000018417d2d0 cfrunlooprunspecific + 392 5   foundation                      0x00000001850b54c4 -[nsrunloop(nsrunloop) runmode:beforedate:] + 312 6   foundation                      0x000000018510f80c -[nsrunloop(nsrunloop) run] + 92 7   nuvem                           0x00000001000e64f8 +[pbafurlconnectionoperation networkrequestthreadentrypoint:] (pbafurlconnectionoperation.m:151) 8   foundation                      0x000000018519ddb4 __nsthread__main__ + 1068 9   libsystem_pthread.dylib         0x00000001967c7dc4 _pthread_body + 160 10  libsystem_pthread.dylib         0x00000001967c7d20 _pthread_start + 156 11  libsystem_pthread.dylib         0x00000001967c4ef4 thread_start + 0  thread 0 crashed arm thread state (64-bit):     x0: 0x0000000100588b80   x1: 0x00000001742f6a00   x2: 0x0000000000000008   x3: 0x0000000196765a74     x4: 0x000000016fd80e38   x5: 0x0000000000000020   x6: 0x0000000000000000   x7: 0x0000000000000fa0     x8: 0x00000001742f6b80   x9: 0x0000000000000000  x10: 0x0000000100584800  x11: 0x00000000005d0bda    x12: 0x00000000fffffff2  x13: 0x00000001887c5480  x14: 0x0000000000000053  x15: 0x000000000000004d    x16: 0x00000001967bda50  x17: 0x0000000000000000  x18: 0x0000000000000000  x19: 0x0000000144d85300    x20: 0x00000001978b7720  x21: 0x0000000000000008  x22: 0x0000000000000008  x23: 0x0000000000000000    x24: 0x0000000000000006  x25: 0x000000000004ffff  x26: 0x0000000144e161d0  x27: 0x000000016fd810e9    x28: 0x0000000144d85300  fp: 0x000000016fd80ed0   lr: 0x0000000100659474     sp: 0x000000016fd80ec0   pc: 0x0000000100659474 cpsr: 0x60000000 

by default nsnumberformatter converts data according current locale settings. in case of simulator uses locale , "." decimal separator. in case of device uses "," separator can't convert data , numberfromstring returns nil.

try this:

extension string {     func todouble() -> double? {         let formatter = nsnumberformatter()         formatter.locale = nslocale(localeidentifier: "en_us")         return formatter.numberfromstring(self)?.doublevalue     } }