Depending on how complicated your API is, you may not need something as heavy as Django. This is a neat little framework if your backend doesn't need to heavyweight:

http://falconframework.org/

It's pretty unopinionated so you have a lot of control and there are less surprises but a lot of the nice to haves are gone as well.

Whatever you go with I would read this as well as the DRF doesn't generate proper RESTful responses on it's own.

http://jsonapi.org/