Make your bike sound like a motorbike

No more playing cards in the spokes, there’s now an engine sound app specifically made for cycling. It works by using the accelerometer on your phone to detect how fast you’re pedaling to match the engine sound revs to your pedaling speed. See https://play.google.com/store/apps/details?id=com.ASLGames.Accelomemer

Sounds like just the job for much commuting hilarity when twinned with some portable speakers………………….