Dual touch controls very inacurate, even with low sensitivity

Hi there!

So I'm making a sniper game and decided to use the dual touch controls prefab included in the Standard Assets. I took out the move and jump panels, added a FPS controller and I was done. Problem is, the controls are VERY inaccurate, even with low sensitivity. The aim jumps around, making sniping impossible. So what should I try to do? Did do something wrong with the Dual Touch controls? Or is there some other script that is more suitable for high-precision aiming?

I know sniping games aren't impossible as I've seen many on the Google Play store for Android, and they work a lot better than mine.

Thanks for your ideas!