Originally released on the Google Play Store, Bat Recorder is an Android app designed to record and analyze ultrasonic audio such as bat echolocation calls. I have retired from active code development, and as such I have provided the code for the app free to all under the GNU license - contributions that improve the app and fix bugs are very much desired and welcome.

The first incarnation of the app was written over a decade ago, which is why the code base is primarily in Java and not Kotlin. If someone would like to do a conversion, that would be great. Also, it would be ideal to have a suite of unit tests.

There was a known bug where the USB driver gets overwhelmed with data on certain devices, causing period skips in data acquisition. This has been fixed by Radek DiLuca (https://github.com/RadekDiLuca) of Dodotronic (https://www.dodotronic.com)! Much appreciated!

Note that to use this code base, you will need your own key for the Google Maps API.