So for my new app I\'m having a URL scheme so that people can launch my app from another app or from a website... \"myapp://\" ... So what happens if there is another ap
Apple's policy has changed since 2012. Today they indicate that multiple apps will not be allowed to register for the same scheme. Registration time is a much cleaner place to address contention than runtime, since it avoids the security issues discussed it other answers.
Note: If more than one third-party app registers to handle the same URL scheme, there is currently no process for determining which app will be given that scheme.
Source:https://developer.apple.com/library/ios/documentation/iPhone/Conceptual/iPhoneOSProgrammingGuide/Inter-AppCommunication/Inter-AppCommunication.html#//apple_ref/doc/uid/TP40007072-CH6-SW1