Pepperfilters - Pepper's Snapchat Geofilter creator allows you to easily create a custom snapchat geofilter for your birthday, wedding or event.
StickersApp - Extract Stickers From Photos
Vidcode - Build your own Snapchat filters with code
Imoji - Turn selfies or any photo into stickers you can text
Snapcode Stickers - Promote your Snaps with stickers
Snapchat Geofilters - Bespoke filters for different locations on your snaps.