SIGABRT error in Xcode 4.6

I'm building an app to demonstrate a point for a project and I keep getting the SIGABRT error whenever I run it I have tried using breakpoints but it comes back to the same line of code in main.m:

int main(int argc, char *argv[])
{
    @autoreleasepool {
        return UIApplicationMain(argc, argv, nil, NSStringFromClass([AppDelegate class]));
    }
}

I have typed bt into the debugger and this is what I get:

* thread #1: tid = 0x1c03, 0x96b38a6a libsystem_kernel.dylib`__pthread_kill + 10, stop reason = signal SIGABRT
    frame #0: 0x96b38a6a libsystem_kernel.dylib`__pthread_kill + 10
    frame #1: 0x9244bacf libsystem_c.dylib`pthread_kill + 101
    frame #2: 0x04a7657b libsystem_sim_c.dylib`abort + 140
    frame #3: 0x04bf6f7b libc++abi.dylib`abort_message + 105
    frame #4: 0x04bf4a25 libc++abi.dylib`default_terminate() + 34
    frame #5: 0x010cf0c1 libobjc.A.dylib`_objc_terminate() + 94
    frame #6: 0x04bf4a65 libc++abi.dylib`safe_handler_caller(void (*)()) + 13
    frame #7: 0x04bf4acd libc++abi.dylib`std::terminate() + 23
    frame #8: 0x04bf5c4e libc++abi.dylib`__cxa_rethrow + 83
    frame #9: 0x010cefbd libobjc.A.dylib`objc_exception_rethrow + 47
    frame #10: 0x01c36f98 CoreFoundation`CFRunLoopRunSpecific + 360
    frame #11: 0x01c36e1b CoreFoundation`CFRunLoopRunInMode + 123
    frame #12: 0x0001117a UIKit`-[UIApplication _run] + 774
    frame #13: 0x00012ffc UIKit`UIApplicationMain + 1211
    frame #14: 0x000021bd Scooter App`main(argc=1, argv=0xbffff378) + 141 at main.m:16

All help will be gratefully received.