Having recently gone over to the dark side (I switched to an iPhone 5s) I was looking forward to trying out a filter called Waterlogue that is only available for iOS. But it is the first filter I have seen (and this includes all the Photoshop filters and most third party filters), that creates a result that looks totally convincing. If you have an iPhone, it's worth every bit of the paltry price.
It's fun to watch as well as the image builds in much the same way an actual watercolor does.
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