While doing background research for the most recent free concerts post, I stumbled upon these John Cage apps.
iPhone users can download the 4’33” app. With this app, users can capture the ambient sounds in their environment and upload them (in three movements). You can also listen to other people’s contributions from a variety of locations around the globe. Sorry, no Android version available. Though the website says it is free, it is $0.99 at the App Store.
iPhone and Android users can download the free Prepared Piano app. The iPad and Android tablet versions cost $0.99 each. With this app, you can play samples of a piano prepared with various bits of hardware placed under and between the piano strings. You can record your own performance, using nine sampled notes at a time (free versions; the tablet versions have 36 prepared notes), and share it. It is noted that these are the actual materials used by John Cage in his Sonatas and Interludes for Prepared Piano.
You might want to explore the Cage website, which includes a recording of his work Empty Words. In this piece, Cage reads from the Journals of Henry David Thoreau, leaving out randomly-selected sentences, phrases, words, and syllables in the four movements (lasting over eleven hours), sometimes yielding an effect similar to listening to Beowulf in Old English. Empty Words runs continuously on the site, so you will come in at a random spot in the piece. If you arrive at a moment of silence, wait, or come back at the randomly-selected time of your choice. Perhaps in four minutes and 33 seconds.
Image attribution: Photograph of John Cage by Rob Bogaerts / Anefo, 1988, Fotocollectie Anefo. Nationaal Archief, Den Haag, nummertoegang 2.24.01.05, bestanddeelnummer 934-2728, via Wikimedia Commons [Creative Commons CC0 1.0 Universal Public Domain Dedication], https://commons.wikimedia.org/wiki/File:John_Cage_(1988).jpg.