It was rumored to feature Dolby Digital Plus surround sound and an HDMI output for media playback.
Based on the leaks that circulated, the X7 was designed to be a "beast" of its era:
It was built to run Windows Phone 7 , featuring the then-new "tiles" interface. Why It Matters Today
The Xperia X7 was intended to be Sony Ericsson’s flagship entry into the ecosystem. At a time when the brand was transitioning from Windows Mobile to Android, the X7 represented a high-performance alternative that ultimately remained a concept or a prototype. Rumored Key Specifications
The X7 is often discussed alongside the , which was leaked at the same time and featured a 3.5-inch screen and a surprising 10.1-megapixel camera.
A 4.3-inch capacitive touchscreen with WVGA (480x800) resolution.
A 1.2GHz Qualcomm Snapdragon processor, which would have been a significant step up from other smartphones at the time.