Tube Chum London is the London Underground alert app. Tell him the underground lines you travel on and the times you travel on them and he'll let you know when there are any delays.
Supports all London Underground lines, including the DLR.
Periodically polls TFL data to discover the status of the underground and if there is an issue on a line you've expressed interest in pops up an alert on your phone.
Perfect for the commuter who would have left work a little earlier (or later!) if only they'd known there were severe delays on the Jubilee line (again!)
-Altered location of data feed with a view to deprecating the current URL. In 1 month (from 20/03/12) only version 4 will be able to get up to date data.
-No longer display closures such as Waterloo & City line as these occur every week at the same time.
-Fixed an error in the tube chum service (was occasionally crashing when doing an update)
-Made more compatible with other devices