The catalogue opens this month with Chess and Rubamazzo, a few apps at a time after them. See the release plan.

Chess app icon

Chess — aiOrion GamesBoard game · First release

Expected October

Chess

A timeless board, a private on-device mind.

Five chess games for one price: classic chess, Fischer Random, Crazyhouse, Wild Armies and the original Four Towers study — each asks for a different way of thinking. A bundled Core ML model ranks only moves the rules engine has already validated.

5 games in one2Apple OS 27iPhone Duo readyNo adsOn-device play
Coming soonRead the rules
Chess game artwork

Learn

Learn the game before you play it.

An illustrated, animated walkthrough of the rules, plus a short read on what the game asks of your mind. Both open here in your browser — no download, no account.

How to play ChessWhat it trains in your mind

A guide for every variant

The rules

How it plays

  1. White moves first; players then alternate one legal move at a time.
  2. Each piece follows its standard movement and capture rules.
  3. Castling, en passant and pawn promotion are supported.
  4. A move may never leave its own king in check.
  5. Checkmate wins; stalemate, repetition, the fifty-move rule and insufficient material can draw.
Availability note. Expected October is an approximate target. The catalogue opens a few apps at a time, and each release waits until the one before it has settled in.

Ways to play

5 games for the price of one.

Every variant here is a game of its own — its own rules and legal-move checking, its own tables, its own illustrated guide, its own daily challenge, its own achievements and its own taught first game that walks you in. One purchase brings all 5. Each option below changes the table while keeping the engine's legal-move checks in charge.

Chess

The classic chess starting position.

  • The standard chess array: each side sets up a king, a queen, two rooks, two bishops, two knights, and eight pawns on the two ranks nearest them, with the white queen on a light square and the black queen on a dark square. White moves first.

Arena

  • Chess Arena — Blitz 3+22 players · solo
  • Chess Arena — Rapid 15+102 players · solo

Tournaments

  • Chess Tournament — Classical • SwissSwiss of 8 · 2 a table · solo

Chess960

Fischer Random — the back rank is shuffled, the same for both sides.

  • Chess960 (Fischer Random) keeps every standard chess rule but randomizes the starting order of the back-rank pieces, freshly for every game.
  • The two bishops always sit on opposite-coloured squares and the king always stands between the two rooks. Black mirrors White exactly.
  • With 960 legal starting positions, opening theory matters far less and understanding does more.
  • Castling follows the Chess960 rule and is available on both wings in every one of the 960 positions: wherever the king and rook begin, castling finishes with the king on the g-file (king-side) or c-file (queen-side) and the rook beside it on f or d.
  • The squares they cross must be empty and the king may not pass through check, so some arrangements can castle almost at once while others must clear the back rank first — and occasionally the king or the rook is already home and barely moves.

Arena

  • Chess960 • Rapid 15+102 players · solo

Tournaments

  • Chess960 • SwissSwiss of 8 · 2 a table · solo

Four Towers

An authored setup: four rooks and one king per side, no other pieces.

  • Four Towers replaces the usual back rank with four rooks and a single king on each side, behind the normal row of pawns — no queens, bishops, or knights.
  • It is a purpose-built example of an arbitrary authored chess position: every standard rule still applies (pawns promote, the king can be checkmated, castling with the corner rooks is available), but the play is dominated by rook activity along open files and ranks. A study in heavy-piece coordination.

Arena

  • Four Towers • Rapid2 players · solo

Tournaments

  • Four Towers • knockoutknockout of 8 · 2 a table · solo

Crazyhouse

Every piece you capture joins your army — drop it back on any empty square.

  • Crazyhouse begins from the standard array and keeps every chess rule, with one addition: a piece you capture becomes yours and goes into your hand.
  • Instead of moving, you may drop a piece from your hand onto any empty square — a drop may give check and may even give checkmate.
  • Pawns are the one exception: they cannot be dropped on the first or last rank.
  • A pawn you promoted returns to your opponent's hand as a pawn when it is captured, whatever it had become.
  • Nothing ever leaves the game, so material never simplifies and no king is ever safe by distance alone.

Arena

  • Crazyhouse • Blitz 3+22 players · solo

Tournaments

  • Crazyhouse • knockoutknockout of 8 · 2 a table · solo

Wild Armies

Two random armies of equal worth — you might field five knights, they might field three queens.

  • Wild Armies keeps every chess rule and throws away the standard array.
  • Each side is dealt one king and fifteen other pieces in whatever numbers chance produces — a wall of pawns, a cavalry of knights, a pair of queens — scattered across its two home rows, freshly for every game.
  • The two armies are always worth the same in material, so neither side begins ahead; what differs is entirely what your pieces can do.
  • Pawns are dealt only to your second row and still promote at the far end.
  • Your king is always dealt somewhere along your own back row, so the shuffle can never hand one player an exposed king — but there is no castling, so whatever shelter it has is the shelter you build around it. Opening theory is worthless here: you have to look at what you were given and find the plan it wants.

Arena

  • Wild Armies • Rapid2 players · solo

Tournaments

  • Wild Armies • SwissSwiss of 8 · 2 a table · solo

Every online table is a ladder. Each Arena table and each tournament above comes at four entry levels — Challenge 10 GC, Contest 50 GC, Championship 200 GC, and a Friendly 1 GC table that returns the coin to everyone who finishes. The higher the entry level, the more places share the reward; aiOrion keeps 10% of a paid table's entries to pay for running the online game, and nothing from a Friendly one.

Make it yours. Start from any of these, adjust the settings the game allows, and save it as your own template. Online tables start the same way: copy one of the Arena tables, then set the entry, the rewards and who may join.

aiOrion events

Events in Chess.

aiOrion's own tournaments in this game, read live from the game server: when the next ones are and how many places are taken. You enter from inside the app; the entry pays for the online game, and winning earns a reward.

Times are shown in your time zone.

Loading the events

Reading the event calendar from the game server…

All eventsAdd the aiOrion calendar

What is inside

Built around the game, not the grind.

01

Bundled on-device chess neural net

A Core ML chess model runs on your device and suggests strong moves — never an illegal one.

02

No clock, or a rapid one

Take all the time you want, or pick the ready ten-minute rapid table.

03

Chess960 castling done right

Castling works on both wings in all 960 starting positions, exactly as the Chess960 rule says.

04

Realistic wood or a plain board

A warm, tactile wooden set, or a clean, distraction-free board.

Next move

Follow the releases.

Explore every title now; the month labels are approximate, and each release waits until the one before it has settled in. The same rules and identity run on iPhone, iPhone Duo, iPad, Mac and Apple Vision Pro.

Coming soonSee all 21 apps
Private local playOn-device AIConfigurable templatesCalm by design