Joined: Jan 2009
Posts: 44,135
Likes: 6,356
From: New York, NY, and High Falls, NY, USA
Bikes: 1962 Rudge Sports, 1971 Raleigh Super Course, 1971 Raleigh Pro Track, 1974 Raleigh International, 1975 Viscount Fixie, 1982 McLean, 1996 Lemond (Ti), 2002 Burley Zydeco tandem
I use a phone, and I'm mostly happy with it. The thing I like best about it is that it costs less than a bike GPS if you take the cost of the phone as a given. (In other words, with or without a bike GPS, I would still have the phone.) I spent ~$80 on a handlebar mount and case (Quad Lock). I pay for the ridewithgps subscription service.
The thing I don't like about it is that it's difficult to operate when the bike is in motion. It's hard to touch the screen without making an accidental swipe. Bike computers have hardware buttons that you just push down or in.
But overall, the setup works well for me. The Quad Lock mount is very positive and safe. It's fairly easy to move from bike to bike.
On long rides, I lash an external battery for powering the phone. On a six-hour ride, it keeps the phone at 100% charged without discharging to empty, even with the screen on 100% of the time.