So I released a game on Samsung Apps on the 1st of November and here are my downloads:
Novemver 1st: 191
November 2nd: 324
November 3rd: 1,268
November 4th: 664
November 5th: 407
November 6th: 128
November 7th: 48
November 8th: 55
Can anyone explain how the downloads started growing from the first day and after the 3rd day it is going down drastically?
I don’t know how Samsung Apps works, I have more experience with Google Play.
Funny thing is that a game I released in June is now getting 150+ downloads daily and it’s the same type of game I released last week but much lower quality.
Probably the weekend effect.
Your app got approved on Friday, it gets into the “new” lists for the 3 days (as probably they don’t approve new apps over the weekend). Your app stays high on the list over the weekend, and on Monday onwards more apps get approved thus pushing your app lower down the list.
Just my opinion 
I’ve seen similar effect when my app got approved on a Friday in slideme market. Was awesome downloads over the weekend.
So, lesson here: try to get your app approved on Fridays on slideme or Samsung . 
of coz, I could be wrong
What you said makes sense, but why is my old game performing better than the new one (it always got at least 100 downloads per day).
The old game has probably gotten a solid footing somewhere.
Maybe it is showing up high for certain keywords, it could be high on its own category listing, or maybe it is highly ranking in certain countries.
Maybe… it’s magic!