The most popular London Underground app currently available with over 1 million active users. Key features are offline routing, a custom shortest path algorithm, and a robust multi-threaded tile viewer allowing for hi-res maps on the lowest memory devices.
The code base was written in modular manner, using Android library projects, to enable multiple other products to leverage the development effort. Currently over 20 other maps have been released using the tile viewer, under the Zuti and A-Z brands.
Native Android apps, with over 20 products released using the core codebase.