https://www.techradar.com/news/windows-phone-dialer-app-is-coming-to-windows-10-but-why

Microsoft is officially bringing its Windows Phone dialer app to Windows 10 proper, judging by the latest build of Windows 10 Insider Preview for Redstone 5. Evidence of the app on Windows 10 was first found by WindowsBlogItalia, which reports deep integration with the operating system (OS).

While the outlet reports that the app previously just showed call history and favorites on Windows 10 proper, it’s now reported that the app has full keyboard support as well as integration with your contacts.