How do you solve the station-less portion of the problem in terms of keeping track of bikes?
You could tie GPS hardware and wireless connectivity to each bike requiring a power source, and I suppose you could get away with a battery refilled by a generator connected to the rear wheel. This will undoubtedly increase your per bike cost basis though especially if connectivity is required.
Or you could just have some sort of simple RFID or QRCode mounted on the bike that is interfaced with a Spin app on people’s phones and you log the last positions of each persons ride so others know where to find the bike. But then you are at risk of not knowing where the bike is in the case of theft.
It’s a very interesting proposition and I look forward to seeing how you guys try to solve it!