At blinkbox Books, we're using Calabash for automation of native Android and iOS applications. It's a great tool, however its API for operations on UI elements and page models differs from similar tools in the Web world. We were not convinced that RPC style of calabash operations is dictated by the nature of native Mobile and that's its conceptually different from automating Web apps.
Inspired by reach experience with tools such as Selenium, Capybara and Siteprism, we have implemented a thin layer on top of Calabash operations, which allows defining page models (aka screen objects) in OO style and makes them similar to the commonly used POM pattern in the Web world.
It works for both Android and iOS, as long as Calabash API stays consistent between both.