Techland has filed a trademark for Dead Stop, and it looks like it may be some kind of mobile game, or application.
The exact wording of the trademark is, "entertainment services and providing an online game via an application for mobile phones and other electronic apparatus." You now officially know as much as I do about what exactly Dead Stop is. It could be a stand-a-lone thing, or maybe it's connected to the upcoming Dead Island Riptide in some way.
We don't much about Riptide, but we have compiled a list of what we would like it to be. You can check that out here.