Heaps of questions from a brand new grapheneos user (opens in new tab)

Hi everyone Writing this on my new (second hand) pixel with grapheneos. Have been watching this project for a few years and stoked to finally be here. I’m getting closer and closer to the online life I want all the time. I have a few questions: 1. Sourcing apps - is it safer to use f-droid (in my case I like the neo-store) or obtainium? 2. For non open-source apps, Aurora or sandboxed google play? 3. Is it OK to use WiFi at my work? Or at the mall? What are the risks? I’ve got a VPN but using...