MicroG is a free software project that reimplements Google's proprietary Play Services. Its core component, Gms Core, allows applications that call proprietary Google APIs to run on AOSP-based custom ROMs such as Lineage OS. It serves as a free replacement for the non-free Google Play Services, often referred to generically as "GApps." Users who want to reclaim their privacy and freedom while still enjoying core Android features can use it, although apps that take advantage of it may still rely on proprietary libraries to communicate with micro G, just as they do with the actual Google Play Services.
Gms Core offers several features. Users can opt in to Google services and extend application support, and it provides on- and offline location services. It is designed to be easy on battery, memory and CPU, and it includes no bloatware. It works on real devices, test emulators and virtual mobile infrastructure. The project is free and open source, licensed under Apache 2.0.
To function, the Android system must support signature spoofing, which allows Gms Core to pretend to be the official Play Services for applications calling Google APIs. Some ROMs provide this support out of the box, and the project documentation explains what users can do with other ROMs. Gms Core also includes the Unified Network Location Provider module, which handles application calls to Google's network location provider. A complete micro G setup also requires a Play Store replacement application, such as micro G Companion.
The current status of implemented APIs is documented on the project wiki, and contributions are welcome. Developers ask users to report bugs with logs, screenshots, version numbers and device information. Users should not contact the authors of third-party apps about issues that may relate to micro G services. Anyone who has a logcat containing sensitive data can send it privately.
Source: Hacker News · Summarized by HeadlinesBriefing