The winner of the Android Arena on All About Android this week was Jason Howell's pick: VoxxBoxx. This app lets you record up to 8 seconds of audio, which then gets sent anonymously to other users. You can also listen to other voxxes from anonymous users from around the world. Due to the nature of the app, however, there is a significant risk of hearing profane or offensive messages.
VoxxBoxx is a very simple and straightforward app. It features an old style interface that looks like an actual wooden box, complete with a real VU meter. Aside from just sending and listening, it has the ability to share a Voxx to Facebook. You also can report inappropriate messages. VoxxBoxx is free, and is available on both Android and iOS.