What is a smartphone? The answer is not so simple, judging by the number of definitions available. In fact, it can be a bit of a mystery.

With the announcement of new ranges of low cost devices at this year's MWC in Barcelona, it's time to ask: what is the difference between a smartphone and a featurephone in today's market?

The differences between the execution of the phones is pretty stark. For starters, the Z is a solid piece of hardware, an object lesson in the fact that you can’t rest on gimmick alone.