This release adds an opt-in GrapheneOS network location client providing location detection based on nearby Wi-Fi networks using a local trilateration algorithm run on the device. It fetches a list of nearby Wi-Fi networks from Apple's location service either directly or through a GrapheneOS proxy.

It currently only has a very basic approach to altitude estimation which we'll be properly integrating into the trilateration algorithm in the near future.

It currently only uses Wi-Fi networks but we'll be extending it with support for using cell towers as a fallback in the near future.

We're in the process of building our own network location database based on scraping all of the cell tower and Wi-Fi data from Apple's service. Scraping all the cell tower data is quick and will be easy to keep rapidly updated. A contributor scraped more than 2 billion Wi-Fi APs over 3 months.

This data isn't copyrightable and Apple freely offers it without requiring authentication. It will be the initial basis for our database, but we'll add other sources including an option to send us data from GrapheneOS devices. We'll provide database downloads to support offline network location.

Source: https://grapheneos.social/@GrapheneOS/114076810453893886