Magazine : 
5 Rules to Choose the Best E-Reader
4. Always in Need of Wireless Data?
Most of the e-readers make you choose between the affordable Wi-Fi model and the premium 3G or 4G model. The best of Wi-Fi e-ink readers are Amazon Kindle, Barnes & Noble Nook Simple Touch and Amazon Kindle Touch. Barnes & Noble Nook Tablet, Amazon Kindle Fire, Apple iPad 2 (Wi-Fi) and Samsung Galaxy Tab 10.1 are considered to be the best among Wi-Fi tablets. Amazon Kindle Touch (3G/Wi-Fi) is the only best 3G e-ink reader and unboundedly Apple iPad2 and new iPad are the best 3G/4G tablet.
