Microsoft seems to be readying a new Surface device for launch this year, and three more devices in 2017. Shubhan Chemburkar, an Indian app developer, says he spotted a number of Surface hints at Microsoft's building 88 during a recent visit. Microsoft has a wall dedicated to its hardware efforts over the years, complete with the Surface Pro 4, Surface Book, and updated Surface Pen and Type Cover.

Recent rumors have suggested Microsoft may be preparing to launch a Surface-branded AIO later this year. DigiTimes reported earlier this week that Microsoft is planning a Surface AIO as an alternative to the Surface Book.

Chemburkar's photos also include placeholders for three more Surface devices expected to launch in 2017.

Microsoft declined to comment.