I'm not the OP, so I'm not sure what particular app they used. You can find links to the official apps here,
http://www.coolrunning.com/engine/2/2_3/181.shtml, but there are others that will work as well. I actually just downloaded some of the podcasts that had the timing included and used those when I did the program. Since then, I've switch to using Endomondo to track my runs.
I'm currently on week 5 of the 100 pushups program, although I've spent two weeks on weeks three and four. I'm not sure how far I'll make it, but I'm still aiming at the 100 mark.