Need opinion about game controls

I wrote and am testing simple game for android.
Wanted to ask people, active gamers because it is not obvious for me.
Now live touch screen controling is working this way:
One touch - one moving to direction (left-right) + simultaneously immediate shot.
Holding touch - periodical firing. Automatically.
I like this way.
Is it comfortable for you?
Make visible controls - too expensive for resources.
Do you need controls yet?
Video (30 sec):