So does the kobo (at least in the US). Kobo devices have the overdrive app installed on them and you can search for and borrow library books from within the device.

Funny you mention this, because Kindle support for libraries was amongst the last. For a number of years after buying my ereader libraries did not support Kindle. They've supported epub since at least 2010, possibly even before.

So does Kobo! https://help.overdrive.com/en-us/9988.html

This was the primary reason I chose a Kobo. You can use the pubic library entirely on the reader.

Only in the US. In Australia, you need a Kobo for that.