...Stockfish is open source (GPLv3 license). That means you can read the code, modify it, and contribute back. You can use Stockfish on your computer or on your iOS or Androiddevice. So you can get world-class chess analysis, wherever you are. The Stockfish engine features two evaluation functions for chess, the classical evaluation based on handcrafted terms, and the NNUE evaluation based on efficiently updatable neural networks.
Str8ts Helper is a browser-based application which helps you by solving Str8ts puzzles. Run on every operating system and also mobile device with a modern web browser which is able to open off-line HTML sites.
Sudoku Helper is a browser-based application which helps you by solving sudoku puzzles. Run on every operating system and also mobile device with a modern web browser which is able to open off-line HTML sites.