NumberPlace Infinity

NumberPlace Infinity is a free Sudoku-style puzzle Chrome extension with a cumulative 1 million downloads across the Number Place series. It delivers endless grid challenges with five difficulty levels and auto-generated puzzles you can solve or customize to your liking.

It supports strategic note-taking and two types of markers (green checks and crosses), a history feature to redo and correct moves, and optional background music. The app emphasizes battery efficiency while letting you create your own puzzles and train your brain anytime, anywhere.