I've just finished work on a new musical instrument for Android devices. It's called Circular Sound, and it's aimed at people who like noise.

Circular Sound is similar to my other recent mobile instruments in that it combines a sampler with custom digital signal processing, and a unique interface. Sounds can be loaded from a configurable directory on the device, or you can play around with the default sounds, which are from freesound.org. Then they are loaded into spheres that are arranged in a circle on the left half of the screen. The left half of the screen is the source audio mixer, while the right half is used to control effects. The effects include waveshaping, granulation, delay, and modulation.

The goal of Circular Sound is to give a simple access point into generating various types of noise that is related in some way to the source sounds provided by the user.

Download it for free on Google Play and shoot me a comment to let me know if you make something cool with it!

UPDATE: I have been unable to continue maintaining Circular Sound, so it is no longer available.

Granular is a granular synthesizer for Android devices. Play it by dragging your fingers around the waveform for the source audio file. You can upload your own audio files, or just play with the sounds that are distributed with the app.

The horizontal position on the waveform controls the location from which grains will be pulled. The vertical position controls the grain size. The leftmost slider controls the amount of frequency modulation applied to the grains. The middle slider controls the time interval between grains. The rightmost slider controls randomness.

Download Granular from the Google Play Store and start making grainy soundscapes on your phone.

EDIT: I have been unable to continue maintaining this app, so it is no longer available

Rendering audio to a file is an important feature of an audio synthesizer, but if the user can't share the file, then it's not very useful. In my second pass on my synthesizers, I'm adding the ability to share rendered audio files using email or text message.

The code for sharing audio files is tricky. You have to tell Unity to generate some Java code that launches something called an Intent. So this code basically instantiates the Java classes for the Intent and the File, then starts the activity for the intent.

Figuring out the code is tough, but you also need to change a setting in your player settings. Specifically, I couldn't get this code to work without Write Access: External (SDCard) enabled in Player Settings. Even if I am writing to internal storage only, I need to tell Unity to request external write access. I'm assuming that the extra privileges are needed for sharing the file.

Here's the code.

public static void ShareAndroid(string path)
{
    // create the Android/Java Intent objects
    AndroidJavaClass intentClass = new AndroidJavaClass("android.content.Intent");
    AndroidJavaObject intentObject = new AndroidJavaObject("android.content.Intent");

    // set properties of the intent
    intentObject.Call("setAction", intentClass.GetStatic("ACTION_SEND"));
    intentObject.Call("setType", "*/*");

    //instantiate the class Uri
    AndroidJavaClass uriClass = new AndroidJavaClass("android.net.Uri");

    // log the attach path
    Debug.Log("Attempting to attach file://" + path);

    // check if the file exists
    AndroidJavaClass fileClass = new AndroidJavaClass("java.io.File");
    AndroidJavaObject fileObject = new AndroidJavaObject("java.io.File", path);// Set Image Path Here
    //instantiate the object Uri with the parse of the url's file
    AndroidJavaObject uriObject = uriClass.CallStatic("parse", "file://" + path);
    // call the exists method on the File object
    bool fileExist = fileObject.Call("exists");
    Debug.Log("File exists: " + fileExist);

    // attach the Uri instance to the intent
    intentObject.Call("putExtra", intentClass.GetStatic("EXTRA_STREAM"), uriObject);

    // instantiate the current activity    
    AndroidJavaClass unity = new AndroidJavaClass("com.unity3d.player.UnityPlayer");
    AndroidJavaObject currentActivity = unity.GetStatic("currentActivity");

    // start the new intent - for this to work, you must have Write Access: External (SDCard) enabled in Player Settings!
    currentActivity.Call("startActivity", intentObject);
}