Units sold: 150 million
If Nokia is anything, it's the everyman's phone brand. So, when the Finland-based company released its 5230 model, a low-cost smartphone, it was a hit among developing and underdeveloped consumer bases across the globe. Particularly, users quickly adapted to the 5230 in India, Brazil and Indonesia when it released in 2009, though let's not dog the device across the board. Nokia's 5230, which has since been discontinued for the 5235 version, was not Wi-Fi compatible but had a two megapixel camera and was 3G ready.