Take turns dropping your coloured discs into the columns. A disc falls to the lowest empty slot. The first player to line up four of their discs in a row — across, up, or diagonally — wins. If the whole board fills with nobody managing four, it's a draw.
The twist: each player gets two bomb discs. Arm a bomb and drop it into a column to blast away the top disc there — yours or your rival's — instead of adding one. Use them to break a threat or clear the way for your own line. Play the computer on Easy, Normal or Hard, or pass the phone for two players.
How many players? One against the CPU, or two sharing a phone.
What are the controls? Tap a column to drop; tap the bomb button first to use a bomb.
Does it need signal? No. Once the page has loaded once, it works fully offline.