Sonys Xperia Z Ultra exists on the very peripheries of what we might call a phone; To that end, Sony has announced a new Wi-Fi-only model of the device for release in Japan, and the press release refers to it throughout as a tablet. Beyond the removal of cellular radios, the Wi-Fi model appears to be identical to the regular Xperia Z Ultra, featuring the same 6.5mm-thick waterproof casing, 8-megapixel camera, and Android 4.2 software. Sony hasnt announced whether this model will come to the US or elsewhere, but itll be available in Japan this week for ¥52,000 (about $499).