Rob McClure met Andrew Goren while teaching a master class at the Arden Theatre in Philadelphia six years ago. Little did the Tony nominee realize how that encounter would lead him to a side hustle as an app developer.

But let’s rewind. After the master class, Goren asked McClure if he taught private students and though McClure wasn’t looking to take anyone new on, a followup email from Goren persuaded him. During their private lessons, they reached singing harmony. “When he was doing it alone, he could do it and the second I would sing the melody or a different harmony with him it would go away—out the window,” McClure tells Playbill. “I remembered struggling with that when I first started singing, too.

“The pain in the butt is that the only way you can practice is if you have someone else with you—someone else who’s a singer who can read music or an accompanist,” McClure says. “And Andrew happens to be crazy tech savvy and was like, ‘There has to be a way that we can help people who have this problem.’”

With Goren focused on technology and McClure advising on the practical and the musical, they created the Harmony Helper app, which officially launched October 29. Based on patented technology, the app is the first of its kind as an individuated learning tool to help singers accurately learn and rehearse harmony for any piece of music. Says McClure, “It’s born out of a real need.”

How It Works
1. Start with the music.
The app is not a music library—it’s better. The app can instantaneously scan and read any piece of sheet music you own. If you have a paper copy, use the camera on your phone to take photos of each page; if you have a PDF or midi file, you can upload it into the Harmony Helper. Type in the tempo marked on the music. Save and use that photo and then check your sheet music for errors by previewing the audio. “It’s like, ‘Hey, why don’t you listen to it before we map out all of your harmony, and make sure that it sounds like what you expect it to sounds like,” McClure explains.

2. Create your part.
Harmony Helper asks questions based on its read of your sheet music. It will ask you to identify your part in 2-party harmony, 3-part harmony, etc. (as many parts as it reads). “It’s going to read that like a music director would and separate out,” says McClure.

3. Listen to your part.
You can listen to the full music of music as it’s going to sounds with every part singing and accompaniment. You can listen to only your part. You can listen to your part at an augmented volume and the melody at a softer volume. The listening experience is completely customizable so that you can learn your notes and then challenge yourself to hold onto them as you add in what you’ll eventually hear when the full group sings.

4. Test yourself.
“I can sing along with it and it will show me whether or not I’m singing the right pitch,” says McClure. The app features a Guitar Hero-like visual format. Each part is delineated by color. Your part is white. Red dots will match with the white line if you sing correctly, or will be above or below the white line if you sing sharp or flat. “If you’re a high school kid who really doesn’t have great pitch, you’ll see ‘Oh I have a tendency to think it’s lower than it is,’” says McClure. “We’ve broken it down into that visual module so people who don’t read music have something to go off. And if you do read music, you have the hard copy of whatever you uploaded, so if you’d rather look at that as you’re singing into it, great!”

Practical APPlications
Though Harmony Helper started in a private lesson context, the applications for the tool range from elementary school kids learning harmonies for choir to Broadway performers learning new music. “I’m drilling all my harmonies for Doubtfire with it,” says McClure.

In fact, “its usage spans a wider net than we had anticipated,” says McClure in amazement. As part owner and artistic advisor, McClure explains use cases (and serves as the first guinea pig) for Goren, founder and CEO, to simulate technically.

For the auditioning actor, Harmony Helper can be a lifesaver. “The process currently is, say I have an audition and Telsey emails me 13 pages of a song that I’ve never heard before and I need to know it by 10 AM tomorrow,” McClure says. “Right now, I text every accompanist friend I have in New York and hope that one of them is available at 9:30 at night on a Tuesday to meet at Ripley Grier so we can rent a studio and they can plunk out all my parts on my Voice Memo app on my phone.” With Harmony Helper the expense of an accompanist and a studio rental—not to mention the panic—evaporates.

McClure and Goren are excited to see the app take off in a professional setting, too. Typically, music directors in the first week of musical rehearsal get mired in the plunking of notes for individual vocal parts. “I talked to my musical director friends because no one wants to take their jobs,” says McClure. “The benefit on the music director’s side is that if they’re able to use it, they can upload everything before rehearsal begins, share these things with you, and then your singers can come in and not waste time on plunking. [They can] get to actual music direction and dynamics and cutoffs and intonation and things that musical directors like doing.” With its initial launch, Harmony Helper focuses on the individual, but these group sharing features will be released in just a few months.

The team was also surprised to learn that the app may help prevent vocal injury for working actors. “Every singer in the world, no matter how good your technique, is in plunking rehearsal and by the end of the day you feel like you’ve forgotten how to sing because your vocal chords [haven’t learned yet] how to jump those intervals,” he says. “If you’re home, you can just gauge and learn and figure out placement” without going full out.

Still, the app was initially conceived to help beginners—and Harmony Helper fulfills that promise. “It’s for the chorus teacher who can say, ‘We’re doing “Joy to the World” for Christmas. Download this app, here’s the password to our school’s folder. You’re on the green part, you’re on the blue part, you’re on the white part,” says McClure. He’s giddy with visions of kids gathered around their phones—in the privacy of their home, in music class, on a break during rehearsal for the school musical, in section breakouts for their a cappella group—all learning harmony.

Though music teachers may worry that an app like this would deter students from learning to read music, McClure says the opposite is true. “If anything, having the app as an audio aid while you’re buried in your sheet music, that’s the only way I’ve gotten better at reading,” he says.

To date, the general public has been helpful in honing the app, testing the Beta version at events like BroadwayCon (that’s where the idea for the sheet music scanner originated) and the development team are constantly tweaking and making updates. McClure may not have been looking for a new student that day in Pennsylvania, but, through Harmony Helper, he and Goren will teach so many more.

Click here to access a free seven-day trial of Harmony Helper, or to purchase a monthly subscription ($4.99), or an annual subscription ($49.99).