I did the introductory 30 minute today; my time was around 30 min and did 1.9 miles. I believe it's a fun way to incorporate a story line to motivate you to run at intervals (zombies chasing you) as well as incorporating your music in your phone.
This is not an advertising really, but if you don't like the weird tones of the C25K randomly interrupting your songs, but instead have people cheering you on and the voices of zombies behind you, than the $1.99 (currently $0.99 in the Google play store) is totally worth it

