Iris looks good, too, and if it's fast and low on RAM consumption as you describe, it'll be great once it works with private key managers, like Alby or nos2x. In the mean time, I don't trust a web app with my secret keys.

Iris has a nice android app that works just fine so far.

I've just installed it and it seems it's not an actual app, but that it runs on the Tor browser?

Yes I think it's a NWA.

I am using Iris w/Alby on Chrome, no need to enter my private key

I use Iris with nos2x. I certainly didn't enter my private keys.

I've tried many times, actually every time I've see a reference about it, and it has never worked for me.

Wow. That's really interesting. I use a Linux laptop Ubuntu 22.10 and the Brave browser. I know the developers have a telegram group that might be able to provide some insight.