Is there in objective-C any way to see if it is possible to do a certain task without risking crash the application?
Other languages like javascript have
While Felix's answer is technically correct, it isn't the whole story.
On the iOS and Mac OS X, exceptions are used to indicate non-recoverable program errors. Exceptions are not used to indicate user error or recoverable errors like on Java.
Any exception that passes through system framework code will leave said framework in an undefined state.. Catching said exceptions and trying to recover from it will lead to memory leaks, undefined behaviour and crashing.