Looks like there's a bug here. The Lv16 weapon upgrade increases the damage of weapons from 400-500 to 2184 which doesn't seem to do x4-5 times damages at all. The sudden jump itself is a bit awkward, making it seem more like a display bug. Pls check this issue.
I love the game concept, and I kinda enjoy the way the screen shakes, zooms in and out, and changes the speed making it challenging (or frustrating LOL). But making the control far too sensitive is just like handicapping the player for more challenge and that is inexcusable. Making an option to adjust the sensitivity or enhancing the control would make this a much better game. Right now it's nothing but a prank on players that no one seems to find funny.
Very amusing but a bit buggy. Just scored over 300000 and got a bunch of achievements but after the gameover it just stopped. :(
FYI, After the score scene I clicked to return to the main menu but instead of going back to the main page it went back to the game where I just died and the game just halted.
 "Notebook Wars 3: Unleashed")
 "Hanna in a Choppa 2")
 "Hexagon")
 "Endless Migration 2 DEMO")
Im trying to fix it! =) Sorry