I follow old tradition and prefer carrying physical lyric sheets onstage. I once tried iPad. It's easy to use. Just place your iPad in a holder on your mic stand and you are all set. In Fact I heard of an application "Tonara" that offers a “polyphonic music following” feature. I heard that the pages turn automatically as you get to the corresponding spot in the score on the basis of audio of your performance. It uses the iPad’s mic to listen to the audio of your performance.
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