There are a flood of photo filtering apps out there. Of course we all worship on the alter of Instagram, but there are a few others I've found that take it up a notch. One of which is iDarkroom.
iDarkroom is basically Instagram on crack, going beyond color filters to provide texture such as paper, light leak & bokeh, vignettes, noise and various frames.
It doesn't have the social element of instagram, but of course you can save and share photos to such platforms. It also costs $1.99, which is chump change for photography lovers. Totally worth it.