I was wondering that Is there something to be done for apps to optimize to view in search results and search engines. Is keyword only thing depend for apps?
In short, yes there is. It's big business for a lot of agencies but the basis of it is quite simple. It's a bit like SEO was a few years back - heavy focus on keyword optimisation with a small focus on design.
There's an article on Moz that covers it in a bit more depth that should help you out quite a lot: