1. Instead of using the Android image provided by the InformIT download, substitute your own image. Be sure that the blocks match how they were configured when you first built this app.
2. In the Blocks Editor, write different phrases in place of Well done, this is your first app. Experiment with the range of language App Inventor uses in converting text to speech.
3. Currently, the text on the button reads I Speak!—rename the text and use one of the different alignments in the Properties.