The promise is a great one: an AI backgammon coach powered by Gnu Backgammon, a top-notch open-source backgammon AI. Yes, it sets you back €10, but for a really good backgammon with an excellent tutor this kind of money is worth being spent.

So I went ahead, paid the price of admission, and got me “Backgammon Coach” by Laurent Picheon.

And am in a state of regret ever since. 10 Euros is not a lot of money, but enough to regret a purchase. Because, yes, someday, when its development is finished, it might become one of the best backgammon apps. So far it is in “developer shares his first attempt as an alpha version” or so.

Normally, I expect an app on the app store to support my native language, German. Particularly a paid app, today, in times of DeepL and Google Translate and ChatGPT and Gemini and … – you get it, for a paid app that is available in a country’s web shop there is no excuse to not have texts in that country’s language anymore. In former times you could say “Oh well, I don’t know this language, what can I do, I’m just a single developer”. Today, “I was too lazy” is the only excuse.

I would have settled for English, but FRENCH?

Anyway, you don’t need to know that much of a language to use a backgammon app, so I reasoned that when having to choose “Doubler” or “Lancer”, the former probably means “double” and the later “play”, and I was right! Yay!

My next unexpected experience was finding out how to change the level of play. Backgammon Coach offers three levels of play, and of course I wanted it to play full force. But there was no way to do this. I clicked on everything that remotely resembled a button. Wihtout success. Only after I went back to the app store to look at the screenshots the developer had uploaded it dawned on me that he believes everyone starts his app in portrait mode, so he “cleverly” decided that when the app is in landscape mode it will always show the board, and when it’s in portrait mode it shows settings, options, statistics. The thing is, my iPad Pro with keyboard is almost never in portrait mode. A classic case of design ideas gone horribly wrong.

So I am happy to confirm that the game indeed has (french) settings!

And if you click on “adversaire” it will offer you a full screen of settings to control Gnu Backgammon. Cool, if I understood any of them. But I did understand that I can switch from the default 2-ply (roughly expert level) to 3-ply (world class level), which I did. Off to play!

I selected match to five points and started playing. With Gnu BG as AI it plays backgammon on superhuman level (you don’t want to know how many BG apps I tried that would play the initial 41 of the screenshot as 13/8, but of course Gnu BG knows the right move). I’m not a fan of how the UI looks, but it feels right, offering undo, asking for a final confirmation after you have selected your move, just like the best apps do. Nothing to write home about, but I have seen many backgammon apps that don’t get the basic mechanics of moving wrong, so: good job.

I transcribed the match to XG2, and can confirm that Backgammon Coach plays a strong game, stayed blunder-free as long as it worked. The only issue it has is that at the beginning of a match, it always doubles in move 2, for some reason. This is always wrong, and often a severe blunder. Still, it managed to get to a PR of about 5 in default “expert” level, and about 4 in 3-ply level (which, on my old iPad pro, is blindingly fast and highly recommended even though some french red text warns you). If you ignore that initial doubling bug, it should be where the best apps are, with a superhuman PR of about 1 or 2. It never blundered a checker move, and never blundered a cube decision except for the first one.

Update: I noticed a setting to turn the Gnu BG cube analysis level from 1-ply to 3-ply. Afterwards the app handles cubes almost flawlessly. (insert whining about french options here), coming to an overall PR of 1.9 in my first match to 5 points that uses these settings..

But there are the crashes. And the weird bugs.

But those bugs… I got plenty of these memory alerts. I got a completely hanging app. By now I had my first 5-pt match without a crash! Yay! But it’s still frustrating…

Coaching feature: as the name says, the app offers a tutor. At any point in time you can press the hat with the question mark in the center of the screen to open the tutor screen:

I have no clue what the french text says, but obviously these are reasonable figures that actually help me – I played bar/22 8/4*, and ai see that this is slightly worse than its suggested move, bar/22 24/20, because I win a few more gammons.

Other bugs: in a match to 5 points, you can re-double from 8 to 16. I couldn’t find out what happens after winning the 16-pt game, because the app crashed.

My final big complaint is about the app’s price, or rather that the app has a price at all. I am not a lawyer, but I am convinced the Gnu public license (GPL) under which Gnu Backgammon, the heart of this app, is distributed, demands that all derivative apps also are licensed under GPL. Laurent, the author, may ask money for it, but he must open-source it as well for others to consume, which is impossible on the app store. And Gnu have a clear opinion on app store and GPL. So basically, this commercial software is illegal, no way around phrasing it that way.

Summary: you get a french-only world class backgammon that is not really beautiful but would get the job done if it wasn’t so buggy. It costs you 10 Euros although it bases on a GPL licensed AI. For this money you get professional apps like True Backgammon, Extreme Gammon, BGNJ that play better, have beautiful UIs, and are actually not full of memory leaks and bugs. The decision is up to you; I personally find it hard to recommend it, although 90% of the apps on the app store play far worse.

The last two updates to the app were 2 years ago and 5 months ago. I have little hope that the app will improve. Which is sad, because (ignoring the legal aspects) it could be a diamond.

ps. secretly I assume that if my iPad would be English the app would be English as well, and that the author just is using French, not English as the default language in case the user’s language is not supported. But I can’t be bothered to find out, sorry.