Another vote for the Quadlock case and mount. I have mine attached to an out front extension and it has been great. Makes for a good system if you want to move the out front extension up and record video.

Used it with an iphone6 and hyperlapse app last winter to document a tour from Santa Cruz, CA to Lemoore, CA.
https://www.youtube.com/watch?v=_ufQGhxcw5Q