Amazon ink screen electronic paper book reader, what is the difference between k4 and k5, which is better?

I gave up the idea of playing electronic paper books because one of them was on sale. Why? The display effect is naturally scum in front of the ipad, but what I want to say is that this effect is really unbearable ... Why do you have to face the experience and technology of this era that seems to be decades ago ... The afterimage is extremely slow. If you plan to enter comics, my suggestion is to give up as soon as possible, not to mention the background gray level. Mature comic resources on the Internet basically need to be loaded for half a day before the display effect is displayed. ...

Generally speaking, the advantages of this product are: 1 portable, 2 can be seen in the sun, 3 can save electricity, 4 can be seen without this product, and the scanned pdf version is still not good, which is more suitable for reading English content, taking it out when taking an ipad, and more suitable for buyers of deep Amazon electronic library. Children's shoes that are more suitable for eyes to see LCD screens are tired (but it is just as hard to see this product without garbage. What kind of trouble is this? ! )

In addition, K4 cancelled the full keyboard and touch screen, so the operation was a disaster. Can you imagine using the back button below to control the cursor arrow? ...

Please adopt