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Steven Brykman:

But how intuitive is any of this? Ideally a mobile app shouldn’t require any instruction at all but should instead rely on established mobile interaction paradigms. Though device/platform specific, native interaction guidelines are rules we should all adhere to, particularly in the enterprise space. This is the common language of mobile. But if any interaction or functionality seems potentially confusing or ambiguous, better to err on the side of over-informing the user as to its correct usage or intent—via button labels, brief explanatory copy, help overlays, etc.

People comfortable using your app when it’s familiar to the construct of their mobile OS of choice. So don’t force them to change their habit.

Like a good joke, a user interface is good when you don’t have to explain it —I totally stole that sentence by the way.