I understand that using a legacy device is typically a bad idea, but I've brainstormed a few ways in which I could hopefully still take advantage of my Pixel 5 while using GOS. Please nitpick and share any potential flaws in my plan.
Aside from physical attacks and hidden malicious code in apk's I install, are there any other threats I should be aware of if I never connect the Pixel 5 to a network or SIM and always leave it in airplane mode? I would like to use the device primarily to store, create, and edit sensitive files.
Is it foolish to transfer apk's to my Pixel 5 via a thumb drive and install them? On my newer Pixel with GOS, I routinely check for updates to apps from the GOS App Store, Accrescent, Obtainium, and the Google Play Store every few days. (I've been following this guide [https://sideofburritos.com/blog/grapheneos-how-i-install-apps/] .) Because of this habit, I would feel comfortable downloading and transferring any updated apk's anytime I notice an update on my newer Pixel.
I can see two possible downsides, but I think I could manage. First, the app(s) would have to be backward compatible, and second, I assume I might have to delete older versions in order to install newer apk's (but I could be wrong). The main app I would wan't that stock GOS lacks is a text editor. Additionally, I might want a music/mp3 player, audio recorder, and KeePassDC or something similar.
I've noticed that legacy devices still receive updates on occasion, but I am unsure of how I could get notified of when these are released other than just checking the Releases page every so often. This isn't the end of the world, but if there is a link to an RSS feed or something that you could share that would be great.
I'm also unsure how I would go about using a signed update package, but maybe it's straightforward I'll be able to figure that out after a update comes out.
Thanks in advance for simply taking the time to read through this!