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My brother Jan Lachauer and I just released the first version of a webapp that let's you draw and edit animated gifs on desktop or mobile devices. The app´s client side is based on HTML5 and JavaScript. The server side is programmed in Python (gif creation and upload to tumblr/imgur). We use localstorage to auto save the drawings on the client side, so you can continue whenever you come back to the app from the same device.
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A video of an early version of the app. A description of all buttons and hotkeys can be found here.
The following features are implemented till now:
- draw in true color with transparency and variable brush size
- works on mobile devices (tested on iPad and iPhone)
- upload your gif to imgur and tumblr
- import existing gifs to edit or view frame by frame
- auto-save in case you want to continue editing later
- fill shapes
- pick colors
- undo
- onion skin (to see the frame before and after)
- copy and paste frames
- hotkeys