Sync Photos in Android Gallery

I have seen several applications that can sync photos to an Android gallery (Picasa for example) and I want to create something similar to myself where I have a remote server with photos and users will be able to access them from separate albums in the gallery (like aforementioned applications). However, I don't know how this can be achieved, or even where to start.

Does anyone know how I am supposed to do this?

My Facebook photos in gallery sync app on my galactic note 10.1