We said Sony Ericsson — even though we know Sony bought out Ericsson’s stake in the joint venture and that the division has been rebranded to Sony Mobile Communications — because the logo in the back cover picture above is clearly the old Sony Ericsson logo. Also, the company seems to still roll out devices with the old branding on its home market.
With the recent naming convention which seems to govern Sony’s recent devices — Xperia S, Xperia U, Xperia P — it’s kind of difficult to keep track of all the codenames and model numbers. However, the backplate pictured above could easily belong to the Sony ST25i Kumquat aka Xperia U or another, so far unheard of upcoming model (included or omitted from the leaked 2012 roadmap).
Photo enthusiasts will be glad to find out that there is a dedicated camera button on the side, just below the power button and the volume rockers. Other than that (plus the speaker grill, camera and flash hole) there’s really not much else to serve as a hint. The top sports a mic hole as well as a 3.5mm headphone jack. If we can trust our eyes and common sense, we can conclude that the phone will sport a sub 4.3 inch display, judging be the ratio between the jack and the overall width of the back cover.