We just heard that Microsoft is about to bring native fingerprint scanner support to its Windows Hello security hub later this summer. This became clear during Microsoft's WinHEC conference and it can be therefore speculated that Redmond's next flagship devices will likely sport a fingerprint reader so as to give users new security options and ways to secure their phones and data.
Interestingly, it's said that Windows 10 Mobile will support both built-in and peripheral fingerprint readers. Modular Lumias incoming? Eh, just a wild speculation on our end...
The first Windows-powered device to support fingerprint reading is said to be the HP Elite x3, which arrived earlier this year. As a reminder, Microsoft's more recent high-end phones—the Lumia 950 and 950 XL, as well as the aforementioned HP Elite x3—have iris scanners on board, which allows easy biometric unlocking.