First Off The Tube (Lite) helps you board the Tube in order to be closest to your exits and interchanges at the chosen station. It incorporates a detailed database of each and every exit and interchange found on the Tube system and works perfectly well while you're underground as it needs no internet connection or GPS information. You can search by line, or just by the station name to find the station you're looking for.
The app also provides information on the closest stations to a number of London's tourist attractions.
The LITE version covers the ten busiest stations only, and a limited number of tourist attractions.
PERMISSIONS: access to the internal card is required because the data is stored in SQLite files and the app needs to be able to read those files.

*** People, for those of you that mark the app down because 'there is no functionality in it': The app is supposed to show you that the full version can do certain things, and this is what it looks like, etc, so you'd not be buying a 'pig in a poke'. It helps you to judge if you like the design, looks, font size, etc, not much more.

Recent changes:
v1.1: Code update to bring this one to be in line with the paid app (now using NAPTAN IDs etc, read up on that if curious.) -- should help w/ any station discrepancies between the modules, which should now all be eliminated.