If you're using rEFInd on a Mac (for example, if you're dual-booting or triple-booting with a Linux OS), you may have found rEFInd worked fine with Yosemite but broke with El Capitan. This guide worked for me to get it going again: Installing rEFInd on Mac OS X El Capitan.
Disclaimer These instructions work for iOS 8 (tested on both an iPhone and an iPad) using Ubuntu 14.04 (Trusty) and Ubuntu 15.04 (Vivid). The instructions will still likely work in other versions of iOS and Ubuntu, but your mileage may vary. What's the problem? If you take pictures with your iPhone or iPad and then […]