Duotone - Convert any photo to a duotone in seconds
Pepperfilters - Pepper's Snapchat Geofilter creator allows you to easily create a custom snapchat geofilter for your birthday, wedding or event.
Photo + Music = Video - Photo + Music = Video (also known as Video Slideshow Editor) developed by Manas Hive.
Vidcode - Build your own Snapchat filters with code
EditedImages - The web's best photoshopped images
Snapcode Stickers - Promote your Snaps with stickers