[Purple Lady]

I tried the android app and here are my observations so far:

There are settings for justification, line spacing and margins, except the margin setting is missing on my Boyue T62. Luckily the default margin isn't too big, unlike the Kindle app which has huge margins even on the narrow setting. You have a choice of light, dark, and sepia themes.

There appears to be only four font sizes to choose from on a rather unresponsive slider. It seems like you need to tap on or drag to the exact spot on the slider to increase the font size, but to decrease the size you can tap anywhere below the current font size. The largest font size on my T62 is still a bit too small. The only font choices are default, monospace and Roboto.

You can set the brightness, but there needs to be a setting to use the current system brightness.

The app didn't do too well with the CSS on my first book. The first line in the Kindle sample of the book had the first line in small caps, and Hoopla left it in normal casing and size. The reason I noticed this is because the first line had a proper name in lower case.

I installed the app on my Nexus 7, my Boyue T62, and my Nexus 5. When I tried to download the same book to all three, I got a message "Sorry, but the publisher will not allow you to download this title to any more devices" on the third device. You're limited to two devices? That's a bit ridiculous especially considering that there doesn't appear to be a way to remove a book from a device. Overdrive doesn't have the same restrictions and they deal with bigger publishers.