This is a port of Simon Tatham's Portable Puzzle Collection, a collection of 36 single-player logic games. I used to very much enjoy playing this on PalmOS, so I decided to take it with me when I bought a G1.
No Play store? Not to worry.
Get beta APK 10282.4 - but be sure to check back here frequently for updates.
License: MIT license (same license as upstream). Note that this applies to the source as released on github and excludes the extra graphics in the APK, both on the Play store and here. (This is an attempt to keep the genuine app distinguishable from the clones full of ads.)