Windows Phone 8 is expected to be announced next month, so there are likely some devices with the software right now. The popular benchmark app WP Bench has been known to discover unannounced phone names before anyone else. The most recent mystery device to pop up is the Nokia Phi.
According to WP Bench the Nokia Phi is running a version of Windows Phone 8, build 8.0.9698.0 to be exact. It’s possible to spoof the name of the device, but the OS version can’t be spoofed. Even if this isn’t a new Nokia device it is indeed running Windows Phone 8. Hopefully it is a Nokia device, and we see it next month.