With good Object-Oriented practices and knowledge of useful frameworks (IoC - Dagger, Roboguice) produced code always have highest quality.
Ability to organize the application data flexibly and efficiently, to have flexibility in development, and very quick in usage. Experience with ORM libraries (OrmLite).
Experience with writing few apps that use Google Cloud Messaging, as well as others Google API's.
I like and try as much as I can be up to date with the newest Android API's as well as Android related Open Source Frameworks
Experience in writing apps that had Facebook integration using the newest SDK. Implementing such features as: Login, Sharing, Inviting Friends.
Familiarity with Android Support Library, which helps writing universal apps which will work and look good on different Android Versions.
Good theoretical and practical knowledge of Test Driven Development, and application testing. Using Android/Java libraries: Junit, Mockito, Robolectric, Fest-Assert, Hamcrest.
Most of apps that I worked on had client-server communication, with either XML or JSON as data format. I am familiar with useful libraries (this makes the implementations simpler) that can be used in such cases like: Retrofit, Gson, Jackson.
Experience most popular Android build tools (Maven and Gradle), to automatize application building process.
Experience in writing apps using Maps and Location Services.
Working with 'Intellij IDEA' on daily bases for the last 2 years. Knowing all the necessary shortcuts for refactoring, code generation etc.
Working with 'Android Studio' from some time. Being very fluent thanks to its similarity to 'IntelliJ IDEA'.
Before 'IntelliJ IDEA' I worked on Eclipse, although I do not use it anymore I still know how to use it efficiently.