Something to keep in mind regarding Amazon’s tablets is that they are weaker hardware-wise than their direct competitors and are heavily integrated into Amazon’s ecosystems, which hurts their versatility a bit.

Anyways, though anki will run just fine on almost any android device: my sister’s old android 2.3 phone doesn’t even bat an eyelash at it, and I use my nexus 7 for anything language learning tasks (anki, wanikani, dictionary lookup, etc.)