Nokia Lumia Icon
Yes, a Windows Phone. We think the Nokia Lumia Icon is the best Windows Phone on the market. Unfortuntely, it's limited to Verizon in the United States. That said, those who are already on Verizon or are thinking about making a switch would be wise to take a look at this beast before snagging the iPhone 5.
The Nokia Lumia Icon offers an impressive feature set that's highlighted by its design and its camera, the latter of which is better than most including the iPhone 5s'. If this phone was running something other than Windows Phone, we would be hearing a lot more about it.
We should also point out that this smartphone is extremely cheap. Amazon has it for $50 on-contract, a steal for a smartphone of this caliber.