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Apples Demand from Developers: 10 Essential Rules
Keep in mind to not plan too much, but keep playing with the design as much as possible and gauge the UI's effectiveness.
It is vital to think of every possible button/element on every screen.
7. Clarity
Make clear to the user what he/she has control over. Jargons would sound impressive to a hard-core techie, but they would lose value to one who has no idea what you mean.
8. Elegance
The implementation of all the above should be smooth. Not only would the user-interface be good to look at it should also be easy-to-use. One such way to do this would be to use buttons that are of 'tap-able' size.
9. Polish the App Icon
The icon represents your App, so make sure it shows the user what he/she can do with it.
10. Honest pricing
Although it is tempting to price the app according to the work you put into designing it, it would be best to price it according to how often the user would turn to it. Test often with subjects, who would give you honest, yet varied feedback.
