One of the biggest gripes I hear from other Z10 users is that there is no WhatsApp. We do know that there is a native app in development for deployment this month. But there is also an alternative coming to market. It is called OpenWhatsApp, and comes from a group of developers that brought it to the Nokia N9 when native support was ended.
Here are a few screenshots:
You can get all the info and sign up for news updates via the OpenWhatsApp website.
Source: BlackBerry Empire