There’s a point where even a company as large as WhatsApp can’t be bothered to maintain apps for little-used operating systems, which is why the company has decided to stop supporting its messaging app on seven mobile platforms: Android 2.1 and Android 2.2, BlackBerry and BlackBerry 10, Nokia S40 and Nokia Symbian S60, and Windows Phone 7.1. WhatsApp announced the decision on Friday, and clarified that, while many of these operating systems had an important part to play in the company’s early days, they now account for a fraction of the market, and WhatsApp wants to shift its focus entirely to platforms that people actually use.