With Centinel Wheel you can turn your regular bicycle into an ebike controllable via smartphone app. The tri-spoke detachable device features a two 180W motors that can accelerate the bicycle at the maximum speed of 32km/h. The motors are powered by 168Wh rechargeable battery which lasts for the distance of 55km. The battery is easily replaceable for longer travel.
Furthermore Centinel Wheel can be connected to smartphone via bluetooth technology. A companion app shows you wheel status, speed, distance covered and battery level. Also you can remotely lock or unlock your electric bike. Pledge $499 to preorder via Kickstarter.
Available at kickstarter.com for $499