When Christopher Kirkley lived in Mali, he observed the locals using their phones to store, play, and trade music. If the sounds that someone is playing catch your interest, Kirkley writes, you can easily obtain a copy “through a very literal peer-to-peer transfer, utilizing the built in Bluetooth capabilities to swap songs.” The MP3s exchanged are often “self-produced, local creations—music composed in a DIY revolution of cheap technology.”

To hear what he heard, you need only order one of Kirkley’s anthologies, Music from Saharan Cellphones (2011) and Music from Saharan Cellphones Vol. 2 (2013). The songs, which are often excellent, feel both local and global: You can hear the music’s North African roots, but it has absorbed many external influences as well—funk, hip hop, even reggae. It’s precisely what you’d expect from the soundtrack to what Kirkley calls a parallel “network of cellphones, travelers, truck drivers, immigrants, and refugees” that “is like the internet, but independent of the internet.” —Jesse Walker