Ask HN: what should I build

Hello fellow HN users. I am addicted to this site. like I have formed some kind of a habbit or something.

I am learning to build websites frontend as well as back end.

I am familiar with php codeigniter, and slim framework. I know css fair enough, and use bootstrap and jquery mostly for front end.

I have made smaller apps which can send sms.

now I would like to ask you for some ideas. What should I develop. I have thinked about it a lot, but I can't think of anything that can add value to user. so insights and helpful comments are welcome.

please forgive me for bad english.