From today’s Wall Street Journal:
The hand-held device, which sells for $99, attaches to a tuning peg on a stringed instrument. After the user plucks the string, Roadie analyzes the sound and automatically adjusts the tension to get the string tuned properly. An app stores profiles for different instruments and custom tunings and keeps track of the elasticity of the strings, telling the musician when new ones are needed.
Too good to be good? Read more here.