you can't get a sim card anonymously here, and i believe that's the situation in other places. and even individuals selling their phones make some ownership transfer papers.

it's very hard to stay anonymous on mobile. our best bet is still desktop/laptop.

How to Take Your Phone Off the Grid: "I set up accounts with [..] Apple". How does this combine?

Privacy on a device that's connected to the internet and cellural network is bit of an oxymoron. There's ways to configure it to be slightly less intrusive but not by much. These tweaks are equivalent to taking off your hi-vis vest; you no longer stand out from a mile away but you're still visible.