Last March I wrote about the need for Android UI design to look more like Android and less like iOS. This is something Google calls Pure Android. Typical violations include splash screens, ‘Back’ buttons, right carets (disclosure indicators) on lists and toolbars at the bottom. I previously wrote of the extra cost to to implement an iOS design on native Android and the further cost as companies then re-engineer to move back to Android idioms.
While an iOS-esque design on Android might not seem a big issue, it is. There usually comes a stage when the problem is how to attract more downloads. Clients ask why the app isn’t working (business wise) for them. They ask for more downloads. My experience on projects (and speaking to others and attending conferences) is that the real issue isn’t downloads but retention – keeping people after they have installed the app. Retention is partly about having an app that feels right on the phone it is being run on. iOS-esque idioms run contrary to that feeling.