Heads up: this browser isn't saving anything for this site, so progress and settings reset when you leave the page. Everything still works while you're here.
GridForge on the web is built the same way as our iOS apps: private by design.
Your work stays on this device
Your progress — best scores and XP — is stored only in this browser (on-device storage). It is never sent anywhere. Clear your browser data and it's gone; nobody else can see it.
No accounts, no ads, no tracking
There is no sign-up and no login. There are no ads and no in-app purchases. There are no third-party trackers. Every computer opponent runs entirely on this device.
Built for ages 9–14
The 400 Concepts questions come straight from the GridForge iOS design. Losing is framed as a pattern to spot next time, never a scold, and each opponent scales to you. A hint appears only after a first try.
Connect Four's report card
We let the engine play Connect Four against itself 1,000 times, dropping discs at random, and counted: 100% of games finished, a typical game took 21 discs, 99.6% ended with a winner, and the player who dropped first won 56% of them, with about 6.8 columns to choose from each turn. Random play is not how people play: with perfect play the first player always wins by starting in the middle. These numbers describe the rules, not players.
Spark & Anvil is a non-profit, 501(c)(3) pending. Apps stay free forever. This page is a plain-language summary, not legal advice.