Surface: Neither the Surface RT or the Surface Pro have a 3G or 4G connection. The only connection offered if Wi-Fi.
Kindle Fire: The Kindle Fire does not have 3G access. It has Wi-Fi access only.
The new iPad: A higher priced version of the iPad allows access on Verizon, AT&T, and other 4G networks off Wi-Fi. The device also has Wi-Fi access.