When downloading APKs outside of the Google Play Store, be cautious of:

Searching for "UHD V399" primarily relates to hardware components like Android TV boxes (specifically those using the RK3399 chipset) or specific software versions for multimedia apps. There is no widely recognized single "UHD V399" app; instead, it often refers to:

Apps like MEGOGO (Live TV & Movies) have historical version releases like 3.9.9 that support UHD playback.

Some third-party apps or firmware are designed for "fake" devices that report higher RAM or Android versions than they actually have.

: A popular alternative marketplace for regional apps and games.

The "RK3399" is a high-end hexa-core processor used in premium 4K UHD TV boxes like the Cloudnetgo CR19 , capable of playing 4K video at 60fps.