Do you sacrifice your privacy by using assisted-GPS?

phonehelp

If I launch organic maps or co maps, sometimes it takes minutes for it to detect my location.

If I turn on assisted-GPS, it reduces that time to less than 10 seconds. However, am I losing my privacy in anyway in doing so?

I believe my phone is pinging cell towers (but my phone is on airplane mode, so is it really pinging cell phone towers) and known wifi signals (wifi is on with airplane mode).

Can anyone shed some more light on the situation?

de0u

phonehelp If I launch organic maps or co maps, sometimes it takes minutes for it to detect my location.

If I turn on assisted-GPS, it reduces that time to less than 10 seconds. However, am I losing my privacy in anyway in doing so?

The privacy implications depend on details of what is happening. Which settings exactly are chosen to "turn on assisted GPS"? A GrapheneOS device might have Google's location provider installed and enabled, and also might have the GrapheneOS network location provider enabled (which has options).

At present all of those have privacy implications, but not exactly the same.

linux-dev

HTTPS connections are made to fetch PSDS information to assist with satellite based location. These are static files and are downloaded automatically to improve location resolution speed and accuracy. No query or data is sent to these servers. These contain orbits and statuses of satellites, Earth environmental data and time adjustment information.

Details here: https://grapheneos.org/faq

This has nothing to do with cell towers, the psds info helps to get a gps fix faster. In layman's terms: without psds your phone needs to receive signals from more satellites until it can determine the location. It works basically like this: if you see a certain satellite at a specific time you must be somewhere located in this area on earth.

Cell towers along with a database would be an additional sources to determine location. Same applies to wifi ap locations and some database. In terms of privacy the worst are online location services where you send wifi mac of the ap or cell tower id.

wonder75

In my understanding - please correct me if I am wrong - it works like this:

The "assisted GPS" will regulary update satellite data. It downloads data from servers (GOS, Google or others). This data is needed to calculate the sat positions on the fly for a fast fix. The "assisted" download does not happen when you turn on your GPS. It already happened before. In your case the "quick fix" worked in Airplane mode because you already downloaded the data recently. Android does this automatically, I am unsure about the frequency of updates.

If you don't download the data in advance from the internet, you will download it via the GPS-signal. The data is embedded into the stream of data GPS satellites broadcast. The downstream is very slow so it can take several minutes for the data to arrive on your device if it hasn't been preloaded over the internet in advance.

de0u

wonder75 In my understanding - please correct me if I am wrong - it works like this: [...]

It depends.

Some information is here: https://en.m.wikipedia.org/wiki/Assisted_GNSS