How to keep score in padel without your phone

Score on your wrist. An Apple Watch scoreboard needs one tap per rally, works with the iPhone in your bag, and holds the match if the phone is out of range for the whole 90 minutes. The alternatives are the club board, which nobody walks to, and memory, which is where most disputed games come from.
Why the phone on the bench does not work
A phone has to be picked up, woken, unlocked and tapped, and it is at the other end of the court. In practice it gets updated every few games from memory, which defeats the point of having it.
It is also the thing you least want in your hand between points. Sweat, glass walls and a hard court floor are a bad combination, and padel gives you about 20 seconds between rallies.
What wrist scoring actually costs you
One tap. The score lives on the watch face you are already wearing, the tap targets are the two pairs, and the app works out the games, sets and change of serve from there.
Undo covers the mistake case. A tap on the wrong pair steps back one point, including across a game boundary, so the honest fix takes two seconds instead of a negotiation.

Working with the phone out of range
Scoring runs entirely on the watch, so a phone in a locker or a bag on the far side of the club changes nothing. The match syncs when the two devices are next together.
That matters more than it sounds. Club WiFi is unreliable, and an app that needs the phone to arbitrate the score will stall mid-set exactly when you need it.
Can you read the score at a glance?
The real question is what you see when you look at your wrist between points. A useful padel scoreboard shows the current game score large, the sets and games small, and which pair is serving. Anything else is decoration you cannot read while breathing hard.
A watch face complication gets that down to a wrist turn, without waking an app at all.

Questions people also ask
Can Apple Watch keep a padel score without an iPhone nearby?
Yes. A watch app can hold the whole match locally and sync it to the iPhone later, so the phone can stay in your bag for the entire match.
What happens if I tap the wrong pair?
Undo steps the score back one point, including back across a completed game or set, so the correction takes a second.