How the scoring works
You score the value of every tile you create, not the number of moves you survive. Joining two 64s adds 128 to your score; sliding the board without joining anything adds nothing.
That is why a careful game beats a fast one. Every merge you set up and then waste is points you already had within reach. The usual advice — keep your largest tile in one corner and never move in the direction that would take it out of there — is really advice about not wasting merges.
One undo, and why only one
There is a single step of undo, for the move you made by accident: the swipe that went up instead of left and buried the tile you were building towards.
It does not go further back on purpose. A game you can rewind indefinitely is a game with no bad moves in it, and the whole tension of 2048 is that a careless move is permanent.
It keeps working with no connection
No account, no leaderboard to submit a score to, and no request to a server while you play. Your best is written to this browser's own storage, which is why it survives a refresh and why clearing site data starts you at zero again.
Once the page has loaded it needs nothing further, so a long journey with no signal is a perfectly good place for it.
Frequently asked questions
Is reaching 2048 the end?
No. When the 2048 tile appears you are told, and you can carry on from the same board — 4096 and 8192 are both reachable if the board is tidy enough. The game only really ends when no direction would move anything.
Why did a 4 appear instead of a 2?
About one new tile in ten is a 4 rather than a 2. It is part of the original game and it is what stops the board from being fully predictable.
Does it save my best score?
Yes, in this browser on this device. It is not sent anywhere, so it does not follow you to another device, and clearing your browsing data clears it.
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