UPDATE: Our recently released Framer Studio solves most of the mentioned downsides below. See: http://framerjs.com

Framer creator here.

The most important difference between Framer and QC is that Framer uses code (javascript) and QC visual programming (patches and noodles). They are very different approaches to define flexible behavior and you should figure out what clicks with you.

If you are just interested in the practical differences, these are the ones I think are key (some of them might be solved/outdated).

• QC has immediate visual feedback. You can get close with Framer by using auto refresh on save (for example with Cactus) but it's not the same.

• QC has better performance in cases where it needs to do heavy computing for each frame (obj-c is faster then Javascript) but generally they are pretty close because the both use the same graphics acceleration.

• QC has a nice set of tools built by Facebook to specifically do UI stuff.

• QC is more extendable if you can code objective-c because it doesn't depend on the browser.

• QC's visual programming is more "forgiving". One typo can break your javascript, QC doesn't have that, there is always some result.

• Framer is very nicely integrated with Photoshop.

• Framers' coordinate and event system is a lot easier (positioning or handling clicks).

• Framer works great on mobile devices (including Android although less smooth)

• Because Framer uses the browser you can re-use things you know like css and html, easily use live data and mix in other javascript things you like.

• Framer is modeled after AppKit/UIKit so is closer to what the actual implementation will be.

Let me know if I missed anything.