Sales in the smartphone market reached 1.2 billion during 2014. GfK has released data from the year and it found sales were up 23 percent in 2014 over the prior year. Phones with larger displays dominated sales--even the iPhones transitioned to larger screens--and Latin America was an important market during the year.

This is the first time GfK is reporting sales in the smartphone industry above 1 billion. Growth won't continue at the same rate but may still reach 14 percent this year (1.368 billion sales).

It's worth noting the data is actually for sales, not shipments. GfK's data is relatively accurate for the whole world given that it pulls real sales data from 90 markets.

GfK reports 2015 will be a strong year for sub-$100 phones, continuing with a trend towards lower average phone costs. Except for some Asia Pacific markets and North America, the average selling price for smartphones dropped last year. That will continue through the current year.

5-inch and larger phones really saw a boost in 2014. Sales of those devices rose by 180 percent and they will become more popular during 2015. GfK predicts they will dominate smartphone sales this year.