As you could guess, the iphone is pretty popular in Japan. I couldn't help but laugh when I saw this application called i-fukkin.
Apparently the work fukkin in Japanese when used as a noun means "abdominal muscles" and when used as a verb it means "to do sit ups". This handy application counts your sit ups, yells koraa! yasumuna! when you stop (means Hey! Don't rest!) and has a cute little Japanese cheerleader to encourage you as you go along. Who needs fitness equipment when you have i-fukkin!
I think the developers of i-fukkin should have researched the name a wee bit more before they decided to call the application i-fukkin. While the application is neat, I think the name may imply much more fun than it really is.
Here is a short, but funny, demonstration.