what is 4G or LTE?

LTE stands for “Long Term Evolution” – it is a radio access technology to deliver Very high speeds-up to 100Mbps (technically) in an ideal environment. 4G is a Standard in Mobile Network Technology and stands for “Fourth Generation”-the latest after 2G and 3G.
4G LTE is one of several competing 4G standards along with Ultra Mobile Broadband (UMB) and WiMax (IEEE 802.16).  The leading cellular providers have started to deploy 4G technologies, with Verizon and AT&T launching 4G LTE networks and Sprint utilizing its new 4G WiMax network.  In terms of mobile devices, many newer Android-based smartphones are 4G LTE capable, and both the iPhone 5 and the iPad 3 are expected to have built-in 4G LTE capabilities when released in the second half of 2012.