What’s one of the best ways to build hype about a new smartphone ahead of its official announcement? According to Google, the answer is simple: have your company chairman use it in public and see how long it takes before anyone notices.

During a recent visit at Allen & Co.'s Sun Valley media conference earlier this week, Google chairman Eric Schmidt was spotted making a call on the not-yet-released Moto X smartphone. The handset isn’t expected to be released until later this year according to Motorola Mobility CEO Dennis Woodside.

In related news, a leaked image from a Chinese microblogging site shows the rear of the Moto X, this time in black. Normally we wouldn’t put too much emphasis on a leaked photo like this but when compared to the handset that Schmidt was seen using, the two look virtually identical.

The back of the phone is curved outwards with a camera lens in the center near the top. Below that is a flash followed by the Motorola logo just below that. On the left side of the camera lens is a perforated speaker grill and on the top edge of the phone, we see what appears to be a secondary microphone hole and a headset jack.

Most believe the Moto X will be highly customizable and given the visual clues in the above photos, it’s pretty safe to assume that the rear panels will be interchangeable. It’ll be just one of several handsets added to the product line, we’re told.