the last number that used whatsapp on my blackberry How do I check the last number that used whatsapp on this my blackberry handset because I downloaded it bt am asked to give the last number that used whatsapp on my phone
As we look ahead to our next seven years, we want to focus our efforts on the mobile platforms the vast majority of people use. So, by the end of 2016, we will be ending support for WhatsApp Messenger on the following mobile platforms:


BlackBerry OS and BlackBerry 10
Nokia S40
Nokia Symbian S60
Android 2.1 and Android 2.2
Windows Phone 7.1
iPhone 3GS/iOS 6


While these mobile devices have been an important part of our story, they don't offer the kind of capabilities we need to expand our app's features in the future. - WhatsApp blog

Check your phone model.