MyMahj is a fun 2D and 3D version of Mahjong that should keep even seasoned players hooked.
The purpose of MyMahj is exactly the same as all Mahjong games - to clear the screen of tiles by clicking on two identical tiles. Only exposed tiles can be removed and the tile becomes exposed if there is no tile over it or if there is an empty space either side of it.
You can play MyMahj in any screen size of your choosing (except full screen) because you can drag the window to the size of your choice. When you first open it, you're presented with a 3D Mahjong board against what looks like a mountainous desktop wallpaper. You can choose from a handful of MIDI soundtracks, which I don't recommend because they all sound pretty much the same.
You can twist the Mahjong board using the mouse, but I don't really see the point in this. You can zoom in and out using the mouse wheel, too. However, it's better just to stick to the 2D view because neither of these are really necessary even if they look good. You have a huge amount of control over the layout too allowing you to change the shape of the board from designs such as 'Castle', 'Canyon' and 'Bridge'.
Overall, MyMahj is a decent Mahjong game although many of the design aspects seem more than a little unnecessary.