In comparison to Apples iPhone, the Android interaction design guidelines are far from being extensive nor are they as regimental. Androids guidelines are comprehensive and clear enough, yet they do allow a little room for some original design creativity – which is good. Of course, there is a reason why there are design guidelines, and they should not be abused (nice to be original though), the guidelines will help you to create a polished and uniformed experience for the user. (You can read more about the Android design guidelines below).
Android GUI Guidelines
Android User Interface Guidelines »The Android UI team has developed guidelines for the interaction and visual design of Android applications. You can view here for articles that describe these guidelines as they are released.
Android Icon Design Guidelines »
This guideline provides information to help you create icons for the various parts of your application’s user interface that match the general styles used by the Android 2.x framework.
Android Widget Design Guidelines »
This document describes how to design a widget so it fits graphically with other widgets and with the other elements of the Android Home screen. It also describes some standards for widget artwork and some widget graphics tips and tricks from the Android team.
DroidDraw : Graphical User Interface Editor for Android
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AnDroidDraw
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