Which Asset Delivery format is best install-time or fast-follow?

Hi,

I was reading Google Play Asset Delivery (PAD) and got confused about which format should we use for our game. The game we are working on is nearly 4 GB in size. And we don’t want to give access to the game application until it’s fully downloaded.

Can anyone help me in this regard?

Thank you

Did you find the best one?

I would like to decrease the size of my update. Would using Fast-Follow decrease the size of my application update in the Google Play Store?