iPhoneography Rule #1:
Textures Make Everything Look Better
One of the easiest ways to make your images look more artistic is to simply layer in a texture and assign it a blend mode.
But the problem is, if you just drop in a stock texture and call it a day, your work will tend to look like everyone else's. It will also feel a bit ... well ... pre-packaged.
Instead, if you can properly bring together a range of textures (perhaps even textures you yourself crafted), each achieving a subtle effect of its own and combining to create serious artistic depth ... that's when it all really starts to feel like ART. That is when you are truly crafting an image all your own.
Compiling textures you design yourself — or even stacking multiple textures from a variety of apps, carefully assigning to each the right blend modes and opacities to dial in the perfect mix — ultimately makes your work more distinctly yours. The artistic effects you achieve will be more under your control, and your compositions will mean more to you.
Once you know how to fashion your own overlays (often made up of half a dozen different textures, each thoughtfully chosen and tweaked to perfection), you will find yourself taking your iPhoneography to a whole new level and getting much more satisfaction from your work.