Annie Mole's, webmaster of Going Underground, daily web log (blog).
If you like this you'll LURVE One Stop Short of Barking, THE fun and informative BOOK about travelling on the London Underground.
The company behind Tube Refund, one of the apps, says that there were approximately 1,996 delays across the Tube network last year (38 delays a week). Hopefully you're not going to get that amount personally, but the which only costs 59p, could pay for itself pretty quickly.
The other app iRefund is $0.99 has fewer ratings than Tube Refund.
If you have an iPhone give one a try, when you're next delayed. They'll make a useful edition to the other London Underground iPhone apps reviewed last year.
"The magic, mystery & sometimes maddening shortcomings of London's Tube are documented with love, enthusiasm & sometimes despair by its unofficial social historian." The Guardian