Education · Philippines
A chess training app for Filipino players, made with FM Deniel Causo — rated puzzles, AI coaches, an opening trainer and a tournament manager. Downloaded 10,000+ times, rated 4.7 on Google Play.
Google Play figures as of 5 October 2026.
A coach can only be in one room at a time, and a lesson ends when the hour does. FM Deniel Causo — a Filipino FIDE Master with a peak rating of 2410 — wanted kids and beginners to keep learning step by step between lessons, from their first moves to tournament play. Generic chess apps are built for everybody, which means they are built for nobody in particular: not his students, not his openings, not his voice.
One app built around the coach. Rated puzzles that follow each player's level, four ways to train them, an opening trainer with spaced repetition, a full analysis board, five AI opponents with their own personalities, an Ask-a-Coach assistant that answers the way Coach Deniel would, his tutorial videos, and a tournament manager for clubs and schools. A React Native app on the phone, a Laravel API and web dashboard behind it, and a free plan good enough to build the habit before Premium asks for anything.
The app is built to get a new player solving within a minute — and to give them a reason to come back tomorrow.
Free on Google Play. Search for Biyaherong Chess.
Email or Google sign-in. It takes less than a minute.
Daily puzzles rated to the player's level — five a day on the free plan.
Drill openings with spaced repetition, play the AI coaches, analyse your own games.
Run a Swiss or Round Robin tournament for a club or school, with automatic pairings.
Every player has a puzzle rating that moves as they solve, and the next puzzles are picked to match it — never too easy, never hopeless.
Daily puzzles, Puzzle Streak where one mistake ends the run, Turbo rounds of three or five minutes, and twelve tactical themes from forks to back-rank mates.
Openings like the Caro-Kann and the Sicilian, drilled with Chessable-style spaced repetition. Premium players can upload their own PGN repertoires.
Engine analysis of any position, with a database of over three million master games to compare against.
Five AI opponents, from beginner-friendly Jaden to Coach Pogi at the top — plus a chat assistant that answers questions the way Coach Deniel would.
Swiss or Round Robin events for a chess club or school, with automatic pairings. Ten players on the free plan, unlimited on Premium.
Real screens from the Android app. Pick one to see it on the phone.
Ask about openings, tactics or strategy and the assistant answers the way Coach Deniel would — in the Taglish his students actually speak.
The same player signs in on a phone app and on the web, and the two authenticate in different ways. Bolting a second login system on for mobile is how accounts drift apart.
One Laravel backend serves both. Laravel Sanctum issues API tokens to the mobile app, the web dashboard keeps a single session cookie, and Google sign-in through Laravel Socialite works for either.
The analysis board needs master games for any position on the board. Calling a third-party database straight from the phone would hand that service every player's identity.
Lookups to the Lichess opening explorer go through our server, which looks up the position without passing on who is asking. The player's identity is never shared with Lichess.
A beginner who only sees impossible puzzles quits; a strong player who only sees easy ones gets bored. Either way the app loses them — and many of these players are kids.
Each player carries an Elo-based puzzle rating, updated with every puzzle they solve, and the puzzles they are served are chosen to match it.
An app with accounts on Google Play has to let people delete them, and under the Philippine Data Privacy Act the data has to actually go.
Delete Account in the app removes the player's personal data from the servers immediately — no grace period — with a public account-deletion page as well. Passwords are hashed with bcrypt.
Captured from the live product — the site, and the app where there is one. Select any screen to enlarge it.
A site that loads fast, answers the question the visitor arrived with, and gets maintained every month instead of ageing quietly in the background.
The manual steps between your tools, removed — quotes, bookings, invoices, reminders and handovers running without anybody retyping anything.
Free to download, with Premium unlocked inside the app. These are the Google Play figures when this page was written.
Figures as shown on Google Play, 5 October 2026.
Open the live site ↗(opens in a new tab)Get it on Google Play ↗(opens in a new tab)
Tell us what is not working. We'll tell you what it would take.
BUSY BUREAU
