Name: Badminton Score - Rally Point Scorer
Author: RiversideArt

Badminton Score follows the rally point rules: games to 21 by default, win by two, and a cap nine points above the target (30 for a 21 point game). Best of 1, 3 or 5 games.

It shows the points, the games won and the serving side, and ends the game and the match by itself when the rules say so.

Controls:
Up button or top half of the screen: point for us
Down button or bottom half of the screen: point for them
Back: undo the last point
Menu: new match (press twice during a match, so a slip does not wipe the score)
The rules are set in the Garmin Connect app, and a match in progress keeps the rules it started with.

One-time purchase with no subscription, seven days free to try, and no permissions asked.