The GT08 is a chinese knock-off smartwatch available for approximately $25~30.
Companion App download
The overall appearance is not bad. Screen is good quality, touch is responsive. Has a camera, but it's crap. Don't know about battery life. Has bluetooth. Has SIM and MicroSD slots. Software (both firmware and companion app) are high-end engrish. Firmware has serious usability problems. (Touch targets, guys! Fingers have a size!!!) Highly dependent on on cellular connection for many features.
The companion app has NOT been updated for Android 5 (Lolipop), and breaks under it.
The hardware looks like a decent platform, but is bundled with crap software. This seems like a feature phone crammed into a smartwatch, with some bluetooth connectivity to get notifications on it.
If anyone has any more information on this device, please let me know! Otherwise, I'm going to try to get mine apart and see if I can pull some part numbers and data sheets.
I've attached a short bluetooth dump produced by android. I couldn't make much sense of it on my first pass, but maybe someone else could.