I buy xiaomi redmi note 3 pro.
Software is: MIUI 8 GLOBAL 6.7.28 / Beta
If nothing apps active, they cost me 1.2 gb of ram.
How?
Sorry for my bad english..
It's the OS itself. Certain things like the launcher and background services are "locked" in to memory. I have at most 1,5 GB of RAM but I'm OK with it since it means the OS is sleek and fast.