Add it to your home screen and it opens full-screen like an app, even offline:
Using Chrome on iPhone? Tap the Share button in the address bar, then Add to Home Screen.
Open your browser's menu (usually ⋮ at the top right) and tap Install app or Add to Home screen.
Tap letters that touch (sideways, up, down or diagonally) to spell a word of 3 or more letters. Each tile can only be used once per word. Then press Submit.
Made a mistake? Tap a picked tile to go back to it, or use Undo and Clear.
Longer words score far more: a word is worth its length × length. 3 letters = 9 points, 5 = 25, 8 = 64. Each word only counts once per game. Used tiles explode and new letters fall in from the top.
Swipe a tile onto any neighbour to swap them. A swap never scores by itself, but it can set up a much longer word. You can even swap while spelling. (Turn swapping off with the switch under the modes.)
Long words leave a power tile where the word ended:
Your high score for each mode and your longest word ever are saved on this device.