Safe ios application from hacking - objective-c

There are ways to determine if your app is jailbroken or if your app has changed (aka cracked). Take a look here and here for example.

From my point of view, everything you get with these methods is a waste of time. Maybe you can make it harder for potential crackers and avoid babysitting babies. But you won't get so far that no talented cracker on earth can crack your app. Even one hacker on earth capable and motivating to hack your application is enough to load it on hundreds of sites.

If really big companies fail at securing their applications, I really doubt you will achieve this ... so: wasted time better spent improving your application.