SoundCloud is a handy app that turns your device into a tape recorder. I recorded messages on my Kindle Fire. I was going to actually try to post something to Twitter or Facebook, but the policies wanted me to agree that SoundCloud could read my Tweets and other things I wasn't totally comfortable with, so I didn't create an account. You can also listen to other audio (podcasts, songs, etc.) from people, famous or not. The British Library had a collection of bird songs.