Click images above for two videos
You should be aware that the latest version of Sonic Pi (2.7) does NOT work with the command line interface detailed below. I have advised the author of this fact, and hopefully it will be fixed in the future. For now you need to use version prior to 2.7 for it to work
Just after I had written the project detailing how you could control GPIO connected devices from a mobile phone using the telegram.app, a reader suggested that it would be nice to add an autoboot option to the project. At the same time, I found a new project creating a command line interface for Sonic Pi. I killed two birds with one stone, and developed not only an autoboot addition for the first project, but also a Sonic Pi Jukebox setup, which lets you use a headless Pi and control it from a mobile phone, tablet or desktop fitted with the free app Telegram. It works best with a Pi-2, but also is ok on a B+)
If you have not already done so, you should work through the first article initially which details how to install and set up telegram on the Raspberry Pi. I have added a QUICKSTART route which lets you skim past the GPIO bit if you only want to do the Jukebox.
The new second article details how to add the automatic boot and logon for both the GPIO and Sonic Pi Jukebox. and details how to install the sonic-pi-cli and the code to utilise it.