The technology I liked the most!!

Kindle!

I think that the main aspect I really liked about Kindles is the fact that it is not affected by the "planned obsolescence".
The idea of having a virtual library everywhere you go is certainly amazing despites the fact that, perhaps, you can carry the same content in a laptop.
The Electronic Ink (E-Ink) is a perfect tool for those who enjoy reading; you don't get tired of reading and as you don't force your eyes it is easy to follow a text.
Kindle App is also a choice but it will depend on the device you have (because of the display resolution)
I have seen this App in some phones and it does not really work.

Anyway, I would buy one of those.