Is it a good enough solution for IMEI tracking to use an alternative device to provide a hotspot connection?
What?
So you wanna use another phone as a hotspot and connect your GrapheneOS Phone to it?
I mean, what exactly do you mean by “IMEI Tracking”? Location?
Well they won’t know the location of your GrapheneOS Phone, but they’ll still know the location of your alternate phone. Not sure what you’re trying to achieve here.
I think you’re a little confused. Connecting to Public Wifi (or any wifi), will not reveal IMEI, it does reveal your Wifi MAC Address, and if you have Bluetooth on, it will reveal your Bluetooth MAC Address, but will not reveal your IMEI (unless you have malware on your phone).
In modern smartphones, including iOS, Android, and especially GrapheneOS, Wifi MAC addresses are spoofed by default, generating a random MAC address for each Wifi network. You can even go to Developer settings of Android to enable randomization for each different session of the same wifi network (or you can “forget” the network and reconnect and, from my testing, it would immediately change the MAC address for that network).
Although, if you have iOS or Google’s Android, you can’t be sure if the companies themselves are tracking you, but but a privacy Android ROM (like GrapheneOS) with Wifi MAC randomization enabled should be very safe.
Keep Airplane mode on so it stops connecting to cell towers.
Your device name and Wifi MAC address is revealed, so change the default “Google Pixel” to something else to hide the fact that it’s a Google Pixel. But, some wifi access points can detect your device model anyways. My Xfinity gateway will show my Phone’s name and what model of phone I have. So I’ll just assume that: Device Name, Device Model, and MAC (which is randomized) is known. Shouldn’t be that much of a privacy risk unless Google Pixels aren’t popular in your area. If there are a lot of Google Pixels around, they can’t prove it was your Google Pixel.