The Android platform has its own unique user experience that Android users are accustomed to, as well as a diverse ecosystem of device manufacturers. Unlike iOS devices, Android devices have a hardware back button and can come in virtually any screen size or resolution created by over 1,300 manufacturers.
The difference though is in the finer points. Native Android app development & design requires knowledge of Java and even the interface changes a bit in order to take advantage of native tools in the Android operating system.
The Android ecosystem is unique in that it is not closed. Almost any device manufacturer can use the Android operating system and can also modify it. Having the standard Android operating system as well as modified versions on over a thousand different devices creates a unique challenge for Android app developers. Understanding the uniqueness of the Android ecosystem gives us an edge, as efficient Android app developers & designers.