Same Mobile here.
i Brought this at Taobao also, but then written there Zivi Z802. But i search online and its exactly HGL MM808.
I've tried to root it, success and then i flash google Framework. But it's failed.
i restart my mobile, everything normal, but the root is empty (auto unrooted)
i try to off my mobile, pressing volume + and power, boot to menu, but when i select recoevery, it bypass and restart, means cannot boot to recovery anymore.
already tried more than 10 times, still failed.
inside is baidu rom, but i guest the manufacturer edited the rom and locked. (i'm newbie)