A/B/X double blind audio testing
This is a simple Android app that performs double-blind A/B/X tests. I wrote it several years ago as a paid ($1) app with no ads. I recently (Sep 2019) decided to make it free and open source for sharing & education.
It is written directly to the Android SDK, not using cross-build tools like Unity. This makes it very small (less than 1 MB in size) and it runs on any version of Android from 2 forward. I build it using Eclipse using the Android plug-in.
It requires / depends on 2 other projects, Util and FileExplorer, both of which are also free open source. I wrote the first and Lamerman wrote the second (https://github.com/kvj/android-file-dialog/blob/master/FileExplorer/src/com/lamerman/FileDialog.java)
More info & detail here: http://mclements.net/clementslogic/abxAudio.html