No, it's open-source.

In order to run it on your iPhone, you'll have to pay Apple $100 per year. Or find somebody who is already in Apple Developer program, ask him to add your iPhone ID.

Someone should start a "iDevBuddy" site, where people can pay a dev for use of her/his unused provisioning slots and install their own software.

I'm pretty sure Apple would consider that a violation of their rules.

Didn't stop people from doing the same general thing in regards to the iOS beta.

Open source apps can be in the app store, like openmbta

No. You need the $99USD/year iOS developer program from Apple to be able to compile it and install it on an actual iOS device (without it being jail broken).