I usually do a 50-ish mile ride about 3-4 times per month, and it takes about 3 hours. I've tried using my iPhone to record the ride, and it died on me before the ride was over. It was in my jersey pocket-- I have a cyclocomputer, so I don't use the phone in that capacity-- and it was probably 95% charged at the start of the ride, but it was still dead before the end of the ride.