Android Editing Keyboard
I do a lot of rich text editing on my phone, but with the standard on-screen keyboard that's a real pain. In the days before Google added text editing features to the standard keyboard, moving the cursor accurately required a very sharp finger, and selecting text was a fiddly matter of finger-dragging little selection posts around the screen.
Even now that the standard keyboard has editing features, none of the shortcuts I'd take for granted on a desktop — Ctrl-X/C/V for cut/copy/paste, Ctrl-B/I for bold/italics, etc — are readily accessible.

So I put this little keyboard together, partly to scratch that itch, and partly to find out just how much fun Android dev isn't. Many of the keys just send Ctrl-something. Some of those somethings are peculiar to certain software I use, so this probably wouldn't be very useful to anyone else.