My general problem with cryptocurrency is their environmental impact / resource usage compared to traditional payment systems.

I dunno, been seeing quite a few posts from https://indieweb.social/@web3isgreat that do kind of give a bad impression…

Having someone else with the decryption keys is not how e2e works. E2E is a pretty solid and proven system, and I have yet to find a solid source about “big tech holding the keys”.

Sadly the same thing has been happening on the android side (a quick google search seems to confirm this). Possible exploits reported but not patched in a timely manner. In general I feel like the Apple bug bounty problem has been swift, although indeed failing from time to time to reward an original reporter. I have not been keeping a close eye on the android side but I imagine the same has been happening. Apple has started to offer e2e encryption on iCloud data blocking even CIA/FBI access. And next to that, seeing I’m based in Europe (and so my data should too) I don’t feel like the patriot act has any impact on me.

I haven’t heard about google testing hardware based attacks on their chips, which I suppose could be caused by android running on a wide variety of chips instead of a few home-developed ones. Next to that Apple has had a bug bounty program for ages, that pays well and covers a wide range of attacks. Not hosting open hackathons has perhaps something to do with public brand image, but Apple shouldn’t be discredited regarding rewarding the findings of bugs and exploits.

Those already exist! Pretty hefty price (compared to your usual ereader) but very much useable. Onyx Boox has a few models iirc