Here’s my personal comparison of Android ebook readers for my Boox eink tablet. I would love to add drawings as annotations. Ratta Supernote devices do this splendidly by storing the pencil input directly, without handwriting recognition. (Example here.) This is the gold standard. Everything else requires multiple apps (to draw a diagram, for example) and import/export (of notes or EPUB book locations), which is also acceptable, but not ideal.
When you use the built-in “NeoReader” on a Boox tablet, you get the best pencil input and quite good highlighting and annotation support. If you don’t have a Onyx Boox eink tablet with that app installed, don’t bother looking for it on the Android/Google Play Store – that app is not available anywhere else, it seems. And the app of the same name on the Play Store is a QR Code Reader.
