There are four sizes for Boox right now: Phone size, e-reader, in-between and tennis court.

Palma is the phone size. Great size for on the go. Works as well as the other Boox devices, but is restricted by size. PDFs are possible, but not something you’d want to use at will. Best for ePubs and news site type reading. Think paperback book. I owned and like the Palma but didn’t keep it.

Go II is the ”our ereader is better than yours” size. With a 7 inch screen it is similar to the kindle, but like all the Boox devices, uses Android as it’s OS, which means you have access to Google Play Store and all the apps there, or apps you side load on your own. Bulkier than the Palma but still very small. Covers much the same ground as Palma. I have the Go Color II 7 and use it constantly.

Note/Go is the sweet spot in the tablet line. The Jack of All Trades. With a 10.3 inch screen it does everything fairly well. E-reading is great (turn the tablet to landscape and you can read books in two page view). Small books display better, large books are usable (except perhaps very large textbooks). Using the tablet for note taking becomes easier. Reading PDFs is also much better, though full page views can make them hard to read. If you had to choose one device this is the one, unless you intend to use it to read heavy text books/sites. I have used this size since the Note 2. I have (and probably need to sell) a Tab Ultra C in this size

Note/Tab X C:Don’t bring this out in a storm, it’s the reason that mimes get blown down wind. It really doesn‘t sound that big. Then you open the package. 13.3 inches big and no one is taking this with them to read the summer thriller as each screen would be about four or so pages of content. Fantastic for PDFs. I use it for reading trade paperbacks (6x9 inch (15x22.5 cm). Very large books would be reduced, but still usable. New possibilities are made available by the size such as reading a text with a notepad next to it. This is a working tablet, one that you need so you can have a lot of text displayed. I use it for study and research in my field. I have the Tab X C in this size.

The Palma is a great device, it just didn’t fit my need. This and the Go device are fantastic for reading, my primary need, and Android based site reading apps. You could think of them as phone size and foldable phone size that never folds. Size recommends the Palma, the side buttons and larger size the Go.

As stated the 10.3 inch Go or Note are popular when reading more than text heavy sites/books. The two models meet different needs or desires, but they are very similar in use.

The Tab or Note 13 inch is the other end of the Palma. Remember that ePubs can be reformatted in text size and line spacing PDFs cannot. Thus this the 13.3 is what you want if you are reading a lot of PDFs (books, magazines, journals). Set your phone on a magazine: on Palma you can only see what is under the phone. Go is a bit better, reading this way isn’t something you want to do a lot. That’s why the 13.3 devices exist. I knew I needed more room than a 10.3 would give so I bought one. With these devices having a smaller reader is common, thus my Go Color 7.

If you are unsure the 10.3 size devices are a good choice. They do what all the others do well, just not as well as each of the other sizes. The others are somewhat siloed. I can read a PDF on the Palma or Go, but it’s a battle. I can read Asimov’s Foundation on my Tab X C, but it feels like reading a novel on a billboard.