What data would I gain access thanks to the PLAY rackets (comparison with POP)? 25 September 2018 20:13 Updated Follow Related articles Do I Need a PLAY racket to use the app? Quick Start Guide Babolat App Why do we only have a percentage of power, and not a ball speed (in km/h or mph) for the forehands and backhands? What is 100% of power for a forehand or a backhand? Comments 0 comments Article is closed for comments.