Johana Bhuiyan and Rani Molla:

Forget the ride-sharing wars. Transportation has a new battleground: Bike-sharing.

After seeing great success in places like China and Europe, dockless or free-floating bike-sharing has started to expand aggressively into the U.S. — but with that comes staunch opposition from incumbent players and, in some cases, the very cities they’re trying to court.

For the uninitiated, dockless bike-sharing works a lot like today’s bike-sharing systems, except you can, in theory, park the bikes anywhere, locking and unlocking them by scanning a QR code with an app. That differs from current bike-sharing programs in places like New York and San Francisco, where bikes are docked to fixed locations.

Dockless bikes are also GPS enabled, allowing companies to easily track and move them around to places of high demand.