I just found this thread. I love the idea of resurrecting my unused iPhone 4. I have a good speed/time/distance computer (cheap wired Sigma that works great), but want cadence (and speed/distance when on the trainer, which I don't get now with the front wheel sensor on the computer). And maybe I'll add heart rate later with a band sensor. I'm a cheapskate, so this seems like a great solution! Since my iPhone 4 is completely wiped clean (I was going to sell it) and deactivated, will I have any problem loading it with the apps necessary to make this system work? RomansFiveEight, are you still using yours, and do you still recommend it? Thanks in advance.