How to Turn Your Phone into a Coach

 Courtesy Tennis Agility Lite

These four apps will help to get you in shape, analyze your swing, care for your racket, and learn the best pro tricks. 

Best for Fitness: Tennis Agility Lite
Loaded with speed and agility drills, many from the ITF, for everything from staying steady on the baseline to getting to the net more quickly. [free; iOS]

Best for Video Analysis: Coach’s Eye
This video app lets you record your strokes and play back in slow motion to improve technique. It’s simple to use, and the videos are easy to share. [$5; coachseye.com]

Best for Racquet Care: RacquetTune
Tap a screwdriver on your string bed and RacquetTune uses the frequency to determine your string tension and stiffness. It’s great for learning how tension changes over time. [$2; iOS]

Best For Learning From the Pros: ATP/WTA Live
This app breaks down every pro match by the numbers, and can help you learn more about your own game by analyzing those of the professionals. [free; iOS, Android]