The rule of thumb for 4G Android phones in 2011 has been that they must be tanks: bulky, rounded-off devices that show exactly what sacrifice you're making to get the faster speeds. Motorola with the reborn Droid RAZR (just RAZR elsewhere in the world) not only bucks that, but has what it claims is the world's thinnest smartphone. However, it's coming into especially fierce competition with the
