What filter did you use on that photo?
Gee, I don’t remember the name of the filter. Heck, I can’t even remember the name of the app that I used. Was it Fotor, Photogene, PhotoStudio, CP Pro, Filterstorm, PS Touch, Camera+, KingCamera, or Film Lab? Imagine if the iOS forced all photo app developers to include the filter information in the metadata of …