The translation and localization management system I initially developed to crowdsource the translation of the apps Complete Ear Trainer, Complete Rhythm Trainer and Complete Music Reading Trainer has just been released publicly as a fully-featured software under the name Cocoon.
You can see more details by going to https://cocoon-translation.com. If you have a game, app, software, website, or any project that would benefit from a crowdsourced translation (or if you want to ease the work of your translators), there is a demo and a free 30 days trial so please have a look!