Here is a nifty accessory for users of Apple Lightning devices. I found this DAC-cable good for situations away from home or with Bluetooth headphones, whenever I would have time to sit and relax in a relatively quiet place and get some high-res listening in.
http://www.hifiheadphones.co.uk/community/threads/v-moda-speakeasy-lightning-dac-cable-review.4537/