Question: I like to become game developer.. I already work as web developer for the past year. There I used php, jQuery, mysql and some framework also. It's little boring now same thing again and again. So I start to learn Android application development.

My question is:

1. If want to become a game developer  

what skills should I have (like
java, c++, etc) ?
2. Where can I get good tutorials (online)?
3. Is previous knowledge will help me?

Answer: 
I would ask you to refer [this](http://www.sloperama.com/advice.html) site. It is the ultimate reference and eye opener for anyone who would like to become a game developer. Let us know if it is helpful to you.
Tank sleep. If you thought 60 hour workweeks were bad before, they'll be distant memories of the easy times pretty soon.

Also, define "game developer". The majority of any programming job is grunt work, programming the bread and butter stuff.
The job "game developer" might appear glamorous to you from a distance, but it's just another programming job (you sound like a junior programmer).
The only difference is that you're programming what happens to a sprite moving across a screen rather than an algorithm to calculate some business data.