Actually, that one port on the left is a usb.
There are three kinds of usb: usb a, usb b, and usb c.
Usb a:
http://img.misco.eu/Resources/images/Modules/InformationBlocks/1210/CTG/CTG-1/15 4636-CablesToGo-1m-USB-4-Pin-Cable-small.jpg
Usb b:
http://www.c2g.com/uk/static/content/images/resources/connector-guides/450/035_u sb_b_f_iso.jpg
Usb c:
http://www7.pcmag.com/media/images/459862-what-is-usb-c.jpg?thumb=y&width=740&he ight=426
And then we have even more after that which are like subkinds: micro b, mini b, etc.
You can simply upload your music from your iPhone 6s to Apple with iCloud or store your music on the "cloud" aka apple's servers and sync to any other device with that same account. If you are truly stuck on the usb then you can also buy yourself a usb a to usb c adapter. Many hubs online also have charging capabilities and a usable usb c still left over with many usb a. Kickshark (http://www.kickshark.com/), a company I started working with, has done that very thing and are producing 2 options for this and many designs still to be released.
If you have any recommendations for products I can actually contact them for you and request it. Otherwise, there are still plenty of easy fix solutions.