Questions

Is it free?

Yes, for now. There's nothing to buy, no card to enter and no ads. Karl pays for the caddie's answers himself, so each player has a daily limit on them; a normal round stays well under it.

Is there an Android version?

Not yet. The Number runs on iPhone and iPad with iOS 18 or newer. On Android, request an invite anyway and pick Android: those requests are kept and counted, so Karl can see how many people want one.

Which courses does it know?

Two so far, with more coming soon. Bala Golf Club in Philadelphia and Philadelphia Cricket Club's St. Martins course in a preview.

Each course is mapped hole by hole from public map data, elevation survey and lidar for the trees. A course counts as confirmed once someone who has played it has checked the map by hand, so courses come one at a time and require curation.

The request form asks which course to map next. Every answer counts as a vote.

How is The Number different from my handicap or GPS app?

It does a different job, so keep what you use now. The app doesn't work out or post an official Handicap Index. It's a caddie: it makes the call for this shot, the club, the target and a short reason, from your own clubs and how you're hitting them today. Why a caddie →

What if there's no signal on the course?

Your yardages keep working. Start the round where you have signal; after that, the distances to the green and the hazards don't need it.

Every shot, score and finished hole you log is saved on the phone and sent when you're back in range with the app open. An “unsent” count shows until then; don't delete the app while anything is unsent.

The caddie's call and chat need signal. Without it, tap Retry when you're back in range, or log the shot and play on.

Can I use it in a competition?

No. The Number is for casual rounds. It works out how the slope changes a shot and recommends a club and a target, and Rule 4.3 of the Rules of Golf doesn't allow a device to do either in a round played under the Rules. Leave it in the bag for club events, tournaments and any other round played under the Rules.

What does the AI see?

What it needs to make the call. For each call or question, the app sends an outside AI service the shot as the app measured it, your clubs and how far you hit them, the notes about your game, your recent shots and anything you type or say to the caddie. Never your name or email address. The privacy policy has the full list and names the companies involved.