BlueScribe is an army list builder for tabletop wargames; it is heavily inspired by and 100% compatible with BattleScribe, reading the same format datafiles and writing rosters in the same format.
Try it out at https://bluewinds.github.io/bluescribe/. It loads and runs in a web browser, no installation or downloads needed. For the moment, it is optimized for desktop machines; while it works on a phone, this has not been tested and is probably a bit finicky. There is no server - everything is stored locally on your computer - and other than downloading or updating game systems, it can be run without internet access. For listing and downloading datafiles, BlueScribe uses the https://jsdelivr.net/ CDN.
There is no tracking, no subscription, no paid features. BlueScribe is GNU GPL 3.0 licensed; you can freely distribute and modify it yourself, though of course I appreciate notice and pull requests if you have improvements!