Boox has rolled out different size eReaders in 6 inches, 7.8 inches, 10.3 inches and 13.3 inches. Entry-level users have better start with small size eReader, and the larger sizes are for professionals.
If you want to read during your trip, camping or any outdoor activity, 6-inch eReader is the best choice for you. If you would like to write, sketch, browse website rather than merely reading, the 10.3-inch screen makes these things more enjoyable. However, the 13.3 inches one is suitable for who desire to read or write on A4 size documents without zooming in.