I rode an ofo yesterday. I had to borrow a phone to do it because it doesn't only need Android but also Google Play which my phone doesn't have. We had to give email address, phone number (entering a code texted to it) and credit card (even though the ride was free instead of 50p/30mins) and restart the app a few times and go into a few menu options before it recognised the card and would unlock a bike. I can't see how you'd hire more than one bike with a phone, which sucks.
The bikes are OK. The saddle has a nice single-handed QR under the saddle and the seat post raises on a gentle spring but doesn't really go high enough for me (6ft) so I was sort of sat in the saddle rather than on it. However, the handlebar reach was about right, so shorter people may feel rather stretched out and struggle with steering. Tannus they ain't.
Unlike London Cycle Hire, the front light is steady, which is good enough for short unlit stretches at slow speeds. There's a front pizza rack with side rails that I think said 8kg max load. The solid tyres do give a very harsh ride, though, much harsher than London's - I'd say it's like riding 37mm at 80psi on an average roadster, but sometimes you hit cobbles and it feels like you're at the other extreme and almost snakebiting.
Controls are sensible: two brake levers, revoshift for the nexus 3 on the right, rotating grip bell on the left, chain guard and kick stand. Gearing is reasonable and possibly even slightly too high for that weight of bike for some bridges and underpasses typically found on cycle routes (the Vauxhall side of Chapel field underpass would be a challenge, I suspect). I rarely got it into top when weaving through the city back streets.
The bike won't win prizes for ride quality but it's forgiving, sturdy and easy enough to ride. What do you expect for 50p a trip?