...I may have just written a Maidenhead Locator generator for Free42 on Android and iOS. Because, you know, there aren't already eleventy billion programs to do that natively on those platforms, so I had to target an overgrown HP-42S calculator emulator instead.
(Fun fact, if someone built a GPS module for the HP-41, and made it compatible with Free42's implementation, you'd only need to change six lines (31, 43, 53, 62 from FP to FRC; 56, 65 from 97 to 65) for it to work on that calc, too.)