Just guessing here, but maybe they just mean "their" feature where they use some internal storage as a swap file or partition and then call it "RAM expansion" or "virtual RAM", and this time they probably decided to call it "big RAM". But that thing is already natively supported by Android since it's based on Linux anyway, it's just that most phone manufacturers don't use it for different reasons (could accelerate wear on the internal storage).

They centered their UI marketing around water:

Aquamorphic Design uses the overarching inspiration of water to blend innovation, adaptability to changes, and intrinsic simplicity into its OS design.

(https://ifdesign.com/en/winner-ranking/project/aquamorphic-design/570747)

Maybe there's some cultural aspect to it that gets lost in translation (and those slides do look machine translated), but I find most Chinese marketing to be really hilarious. I really hope to get an explanation one day as to why marketing is the way it is in China.

Yah I loved my 3 coming from a stock nexus 6. Upgraded to 6t and it was meh. In screen fingerprint was cool I guess.

Now I'm on Graphene which only supports pixel and love it. Did away with all the easy unlock methods as I upped my security game.

I do miss the V to toggle the flashlight though.