Pepperfilters - Pepper's Snapchat Geofilter creator allows you to easily create a custom snapchat geofilter for your birthday, wedding or event.
Vidcode - Build your own Snapchat filters with code
Snapcode Stickers - Promote your Snaps with stickers
Snapchat Geofilters - Bespoke filters for different locations on your snaps.
ARGear - The easiest way to add Snapchat-like AR features to your app
FiveFilters PDF Newspaper - This is a free software project to help people create printable PDFs from content found on the web.