I use ReadEra as well, I haven't found a format it can't read, it has a fantastic UI that makes it really easy to find stuff, it will save your place and also has bookmarks to save specific pages and it's free version has zero ads, literally none at all, which is absolutely insane for how feature rich it is.
So I even bought the premium version, even though it doesn't offer a hell of a lot more it's just such a fantastic app I felt guilty not paying the tiny bit, the Dev really deserves it.
The font type and size was the real seller for me, completely forgot to mention in my OC, I have low vision so reading regular books has become a real struggle.
+1 for ReadEra! Besides .pdfs, it covers a lot of ebook file formats, like .epub, .mobi, .azw3, etc. I typically download .epubs because you can change the font and font size, as well as use dark mode quite easily that way. And it looks like the most recent update now has TTS available for Premium users. It's a very solid app, and is my top choice as well