Phd computer science I m glad to be here.
I m planning to start a phd in computer science, but i cant find a computer science field to fit my needs.
I am working on web applications and app applications over 7 years. I know php mysql jquery java javascript and asp. Furthermore i am working on setting up servers. 
My supervisor want some proposals as regard my phd subject.
I need a field that i can search new things and offer my services to the science.
Can you help me?
These are a possible recommendation based on your experience. Again, such questions are considered shopping question here in academia.SE. Caution: This is not an optimal set of topics you might be interested in.


Information retrieval (text, multimedia)
Search Engine Optimisation
Database ontology
Information security over the web
Data mining (This is a vast area, converge to something relevant)


Hope, this helps!