Liftoff for now. It's the least buggy Android client I have come across. I definitely prefer Memmy on iOS though.
Matt
They are not ready for regular use yet. Performance is poor and battery life is bad. It's fun to play with my Pinephone and watch the software slowly improve, but there is no way I could use it as my primary phone.
I hope they bring the Fairphone 5 to the US in a reasonable amount of time, because the 4 is just too old for the price being charged.
Audiobookshelf works great and is very easy to setup using Docker. I get most of my audiobooks through Downpour. They have a subscription that gives credits to redeem for audiobooks similar to Audible, but they are drm-free. I download the audiobooks and move them to my NAS that has Audiobookshelf running on it. Audiobookshelf has a web client and apps for Android and iOS (TestFlight beta).
That's one of the most significant reasons I stopped using YouTube Music.
I’ve been using Runbox for a couple of years and agree the web interface is lacking. There were also multiple significant server outages last year, but it has been much more reliable this year. As long as you don’t use the webmail often, Runbox is a good affordable email provider and is great for families due to the low cost of sub accounts (additional users).