I splurged on
Sokoban for my phone yesterday evening.I love Sokoban; I can play it forever! There is also a
free version of Sokoban for phones out there that I had for years, but the new one can import new levels. The interface is not as good as on the old game though. As there are thousands of levels to be found on the Interweb I can now have fun until either me or my phone dies.