Here is more info.
lol I'm surprised Public Mobile does not advise people to be careful with speedtests.
It takes a couple days for the "3G" performance cap to be uniformly imposed on new accounts.
Until then, new customers curious about network performance often run speedtests - and often burn through their GB after just a few minutes of dense data spamming across unthrottled LTE. It's not a pitfall most people ever consider - until they suddenly find they've completely consumed their 30-day data allotment - then wrongly accuse PM of cutting them off or ripping them off.
I keep mobile data turned off when I'm not actively using it.
I disable all app permissions to data (and updates, sync, location, etc) then allow apps to access these things only when I'm actively running them.
I don't need my phone to constantly send me instant notifications of every email and social media comment and update. These things can all wait until I actually want or need to see them, the apps don't need to constantly trickle away my data (and my privacy) in the background.
I also use scriptblocker and adblocker on my mobile browser. It claims that after about six months it's blocked roughly 150K incoming objects (which I don't want or need to see anyways), saving me an estimated 5 hours and 2.5GB of data.
I use duckduckgo, cookie autodelete, sandboxie, a different default DNS, and a mobile firewall. These things may not actually do anything useful in terms of privacy (because of the way wireless networks operate) - and I don't even bother with Tor or a VPN (because same reason plus they add latencies) - but all these things do help to obstruct or limit incoming data packets and outgoing data telemetry I don't allow on my device.