I don't know, on the rare occasions I use email on my Android phone, I use K- 9 Mail, which seemed to be the most trustworthy-looking IMAP client in their walled garden. They certainly don't have Claws, and I doubt that Thunderbird would run on the average phone. I don't recognise any of the newsreaders as being familiar Open-Source applications and haven't tried any of them, maybe someone else here has.