How often do people update their data?

Not often. A call to the JSON endpoint once a day would probably be more than enough.

Do I need an API key?

No.

How can I follow changes/developments?

This documentation is maintained on GitHub https://github.com/ThreeSixtyGiving/getdata

As the documentation changes we will publish a changelog on the home page.

How do I report bugs

Please use the GitHub project: https://github.com/ThreeSixtyGiving/getdata