Board.KolibriOS.org

can any one make a application store from where applications can be downloaded and installed while running kolibrios

Yes, this is not complex. But do we really need such app? All apps that were created for KolibriOS can be stored in ISO image.

I have plans to work on something like this. Although that would be more along the lines of "package manager" rather than "appstore", but I think the distinction is blurred anyway.

This is already being done somewhat for installing Netsurf on KolibriOS.
If things work out in there, the core could be used and extended to other applications and libraries.