Tiffen, the filter people make some quite sophisticated filter simulation software. DFX, originally priced north of $300, had great reviews but was out of my reach. Early on (iPhone 3) they released an App which is a LOT like the DFX software, Photofx. For $3.00 it seemed to have about 95% of the capabilities of the $300 software. It was my second purchased App, right after PhotoGene.
I took this image at a favorite location not far from my home because I could faintly see the Olympic Mountains and also for the yellowish glow in the clouds. Unfortunately neither showed. While having a cup a bit later I realized the Olympics would be a no show regardless of what I did but that I could do something about the color. Photofx has a range of Grad Filters. I just kinda dialed in the amount of darkening I wanted in the foreground and the colors were right. A little diffusion filter to make the image softer, more dreamy and I was about done. I framed it with another App, LiveFX and signed it with Impressions.
When I had a chance to download and look at this image on a larger screen the only change needed was to go back into Impressions and reduce the opacity of my signature so it would be less distracting. I'm considering removing those branches in the upper left...haven't decided yet.
Total time less than 10 minutes. Ain't the iPhone fun folks?