Free
$0
- Unlimited play against the engine, 1400 to full strength
- Unlimited online games over Game Center
- Five tactics puzzles a day
- One Rush run a day
- Three positional, three endgame, three Guess the Elo a day
- No advertising, ever
Arte Soft presents
ChessTrainer
The training half of getting good.
Tactics · Judgement · Endgames · Rush · Guess the Elo · Play · Online
Reel one — the engine
Stockfish, compiled in, running on your phone.
Not a server that answers when it feels like it. The strongest chess program there is, on the device, offline, at full strength — grading every move you make while the game is still going.
Reel two — the library
Fourteen thousand positions that all have a point.
Every puzzle has exactly one answer and no branches. Every endgame label was checked against a deep search rather than remembered. A trainer that teaches you something false is worse than no trainer.
Now showing
Nothing leaves the phone.
No account, no analytics, no advertising, no server of ours anywhere in it.
The premise
Nothing will make you a grandmaster on its own. What this gives you is the training half of it — structured, measured, and honest about where you actually are.
Most chess apps are a puzzle feed with a rating attached. This one is built around a different idea: that improvement comes from being told, immediately and specifically, what you missed and why it mattered — and from being asked the same question again a week later, before you have quietly forgotten.
So every mode grades you while you are still in the position, in words about the position. Not “−1.4”, but the rook belonged on the open file, and now it never gets there.
14,351
tactics puzzles
rated 760 to 2800
116
positional exercises
no forced win in any of them
15
endgame drills
every label engine-verified
1,624
rated games
for Guess the Elo
31
languages
chess vocabulary translated, not guessed
0
bytes sent anywhere
there is no server of ours
The programme
Seven ways to be told the truth about your chess.
Two of them are free forever, because a trainer that will not let you play chess is a demo. The other five are the part that is sold.
I
Tactics
Positions with exactly one winning move, and a verdict the moment you play it.
Five a day on a free account.
14,351puzzles, rated 760 to 2800
II
Positional judgement
No forced win exists. Say who stands better, and then find the move that says why.
Three a day on a free account.
116quiet positions, engine-screened
III
Endgames
Canonical positions, played out against an engine that defends properly.
Three a day on a free account.
15drills, every label engine-verified
IV
Rush
A timed run. Solve as many as you can before the clock takes the rest.
One run a day on a free account.
V
Guess the Elo
A real rated game, played out move by move. How strong were these two?
Three a day on a free account.
1,624rated games, 800 to 2599
VI
Play & coach
A full game at a strength you choose, with every move of yours graded as you play.
Free, unlimited, always.
VII
Online
Two people, one clock, no engine anywhere near it.
Free, unlimited, always.
The film
The Opening
A minute of chess, shot the way the game deserves: one warm light, a board in the dark, and the moment a knight settles on f7 and the game is already over.
Reel 1 · 1:12 · in production
The Opening
The title film is being shot. When it is cut, it goes here — in this frame, with captions, and set to load only when you ask for it.
The engine
Stockfish 18, compiled into the app.
The coach is not a heuristic and not a language model with opinions. It is the strongest chess program in the world, searching the position in front of you, on your device, with no network anywhere in the loop.
Move grading uses win probability rather than raw centipawns, because losing a hundred centipawns when you are already up a queen barely matters, and losing them in a level position is decisive. A trainer that shouts “blunder” when nothing happened stops being worth listening to.
Privacy
It collects nothing.
No analytics calls. No advertising. No third-party tracking of any kind. No account to create and no server of ours for anything to be sent to. Your ratings, solved puzzles, review schedule, streaks and game history are stored in the app’s own container on your device, and deleting the app deletes them.
Online play goes through Apple’s Game Center, which carries the moves between the two devices; in a match your Game Center nickname and your in-app online rating are visible to your opponent, because that is what a game between two people needs. Purchases are handled entirely by the App Store — we never see your payment details.
What it costs
Playing is free. The training is what is sold.
Metered rather than locked. Nobody pays for a trainer they have not used, and a mode that refuses to open teaches nothing about what is behind it.
Chess Trainer Pro
Monthly
$3.99/month
- Every daily limit removed
- The full library: 14,351 puzzles
- Unlimited Rush, positional exercises and endgame drills
- Unlimited Guess the Elo
- Everything in Free, unchanged
One-off unlock
$49.99once
- The same, bought outright
- No renewal, no expiry
- Restores on your other devices
Prices shown are US App Store prices. Your local price is set by the App Store. There is no annual plan in between, because a third price is a third decision to make at the moment somebody wants to solve a puzzle. The whole story on pricing →
Questions
The four that get asked first.
- Does it need an internet connection?
- No. The engine, the puzzles and your progress are all on the device. The single exception is online play, which needs Game Center to reach the other person.
- Is there an account?
- There is none to create. Your ratings and history live in the app’s own container on your device, and deleting the app deletes them.
- What is free?
- Playing is free and stays free — against the engine and against a person, unlimited. The free tier also gives you five puzzles, one Rush run and three each of the positional exercises, endgame drills and games to judge, every day, resetting at midnight.
- Why is there no advertising?
- Partly taste and partly licence. The app links Stockfish, which is GPLv3, and compiling a proprietary advertising SDK into the same binary would make the combined work undistributable under that licence. Selling the app is fine — the GPL has never forbidden charging — but bolting a closed SDK onto it is not.
Fin.
Find out what you are actually rated.
Requires an iPhone or iPad. Free to download. Free software under the GNU GPL v3.