Demonstrate, an iOS app developed by Chennai based developer NFN Labs (that stands for Noef Fing Name- say that really fast), gives you a simple way to build a mock-up of an app and share it among friends and colleagues. It is particularly suited for those of you who have an app idea planned out and know what it should look like and what it should do. At this stage, you can use Demonstrate to program the way your app behaves, without actually requiring any coding experience.
It's very easy to create linked areas/buttons in Demonstrate
(Left) Using Demonstrate to work with all the screens that your app will have; (Right) Choosing the transition effect between the screens.