Whether you fancy yourself the second coming of Pavarotti or just the best vocalist in your own shower, the truth isn't always pleasant to the ear: not everyone can sing. Everyone, however, can learn to sing better -- and that's the point of Voice Tutor, a sharp app from the experienced vocal coaches at IMPACK and Kimad Productions. For US$4.99, it lets your iPhone or iPod touch provide a full menu of workouts, fixes, and expert tools for polishing your voice and fi
