Likely the most anticipated After Effects add-on would be Paint & Stick. You probably have seen an advanced look at Paint & Stick and what it offers to do in After Effects. The tool has been in private beta testing for a while, and now there is a short-run public beta, where you can download Paint & Stick for free and try it out without restriction until December 31, 2015.
Paint directly in comp with your custom and Photoshop brushes plus onion skinning. “Stick” your paint on 3D renders.
Paint & Stick makes the promise that After Effects Paint Tools were never able to deliver — It could be the Ae paint solution that everyone has been clambering for.
With Paint & Stick, you can paint directly in your After Effects composition, using custom brushes, or even photoshop brushes. You are able to onion skin you paint elements, making it much easier to create hand draw, or hand painted animations right within the Ae timeline.
The “Stick” portion of Paint & Stick is the fact that you can glue your paint strokes onto 3D renders. Paint on one frame and it will stick to the whole animation. It really feels like magic.
There are no restrictions to what you can use the beta for so feel free to use it on any project, just keep in mind that it is still officially a beta version and that it will expire. The beta plugin will expire on Jan 8, 2016 and will not be able to be used afterwards. After this date aescripts + aeplugins will either ship the full version or issue a new beta so your work will not be lost and you will have options to continue using the plugin.