There was no announcement by Google about the Nexus 5 (2015) at the company's annual I/O developer conference, but with the unveiling of Android M at the event, the next-generation Nexus device has been widely expected to come with all the new features to be introduced in the latest iteration of its mobile operating system. However, Google has surprised everyone by featuring a Nexus 6 running Windows Phone operating system on its SmartLock website.

Google seems to have got into the habit of accidentally leaking the new Nexus smartphone in its videos. This week, in one of the company's Google I/O-related developer videos explaining Android Pay payments and discussing native fingerprint scanning support of the new Android M operating system, a red Nexus 5 was spotted with a fingerprint scanner on the back next to the camera sensor.

Google has now gone on to display an image of a Nexus 6 dual-booting Android and Windows Phone showing Netflix running on the device with the iconic Windows Phone UI on top. The image has been spotted on the on Google's SmartLock website, a dedicated landing page that shows how users can keep their Android devices unlocked when it's safe, and locked when it's not.

Google will reportedly introduce two Nexus phones this year made by LG and Huawei, both of which are expected to come with Android M preinstalled. But the image of a Nexus 6 running Windows Phone has created quite a stir and raised speculations of Google planning to build a Windows Phone under the Nexus brand. Nevertheless, the idea of a Nexus 6 dual-booting Android and Windows Phone appears to be a far-fetched one. Google is yet to make an official announcement about the Nexus 5 or the video, but stay tuned for more leaks, news and rumors that will continue to come in until then.