Line Umpire
Live line calling for tennis
Price history
About
This app uses your iPhone to call tennis lines in real-time. It alerts you with a flash and sound when a ball is out, and can sync with Apple Watch for vibrations and bounce images. Multiple devices can be connected for comprehensive line coverage.
What's New in Line Umpire
3.0
June 22, 2022
The line detection is now better and faster. There is also a new court detection mode available, currently in Beta. It will automatically detect the court, and which line to monitor. It will also measure approximate distances, and speed of the ball.
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FAQ
How does Line Umpire call lines in tennis?
Line Umpire uses your iPhone's camera and on-device intelligence to detect when a tennis ball is out. It then alerts you with a visual flash and sound.
Can Line Umpire be used with an Apple Watch?
Yes, Line Umpire offers Apple Watch integration. Your watch will vibrate when a ball is out and can display a snapshot image of the last bounce.
How many devices can be connected with Line Umpire?
You can connect up to eight devices to each other for a line calling session. This allows for more comprehensive coverage of the court's lines.
Does Line Umpire require an internet connection?
No, Line Umpire leverages on-device intelligence and does not use any internet resources. This makes it fast and ensures no data is uploaded.
Can I review line calls with Line Umpire?
Yes, for each bounce, you can watch a frame-by-frame replay to verify the line call made by the app.
Is Line Umpire suitable for all iPhones?
Line Umpire works better on newer devices where it can perform more observations and calculations quickly. Older devices may have limitations.
Does Line Umpire have ads?
No, Line Umpire is ad-free. It does not contain advertisements, allowing for an uninterrupted user experience.
How often is Line Umpire updated?
The latest version of Line Umpire is 3.0, last updated on June 22, 2022. Updates typically focus on improving detection algorithms and device compatibility.
