Hi @novacane MicroG is a ‘replacement’ for Google Play store. Some apps require Google play service to work on Android phones. Since ours is a ‘Google-free’ phone we do not install GAPPS. MicroG helps mimic the Google Play store and gets most apps to work. There are some limitations though…Not all Banking Apps will work with MicroG there are some workarounds but as mentioned before not all Banking apps will work. Similarly a number of paid apps have issues with MicroG.
We do not have documentation on MicroG on our site or on the wiki. You can check their website for details.