I apologise if I've put this in the wrong section. I'm currently planning a web app which I want to create with HTML5. I know there's lots of HTML5 development tools/frameworks out there but I was wondering if anyone has views on which would be best for me to use considering the following criteria.

1) I have limited HTML/CSS/Javascript experience (I'm an AS3 programmer by trade) so the simpler the tool to use the better, however I will want to be able to get into depth, something which is literally drag and drop will probably not offer enough for what I want.

2) A framework/tool set that has backend/cloud integration would be great, I'm thinking something like Parse.com but for HTML5.

3) Needs to be free or as close as (I already have the creative cloud CS6 though if that's an option).

Thanks for any advice!