Apple is running a secret project, condenamed Marzipan, which will allow developers to build a single app that will work Apple's smartphone, tablet and computing devices. This will likely help bolster the offerings in their macOS App Store which is languishing behind its iOS sibling.
The Bloomberg report that revealed this says their sources be live the new apps will start coming next year, after it is officially announced during Apple's Worldwide Developer Conference.
This move makes sense. The faithful core of Mac users has been saying for a while now that they've been neglected by Apple as iOS devices have made the company into a massive juggernaut. And developers who get onboard will get an extra revenue stream as their apps become multi-platform.
If this rumour holds true, it will take a while for apps to make the change. There are lots of iPhone apps out there that don't work well on iPads. And devs are already under pressure to update their iOS apps to take advantage of the iPhone X's new display.
That said, a more seamless cross-device experience would be a great for users. My favourite cross-platform app, Pixelmator, works well on both iOS and macOS devices but the inconsistency in the UI across platforms can be jarring. If Marzipan mandates feature consistency across platforms then it will be a good thing.