Will WWDC bring a new dev kit allowing devs to port iPad apps to the Mac? Possibly. The roadmap could be a port to macOS from iPad this year, from iPhone to macOS in 2020, and finally a single binary for all devices in 2021. I don't think there's any doubt this is where development is headed. What does this mean for traditional Mac developers? How much functionality will be lost on the Mac in the transition? I'm not looking forward to a few rough years.
Apple Plans on Combining iPhone, iPad, Mac Apps by 2021 by Mark Gurman