Rochelle Clarke spent four years traveling as a consultant. But her business idea didn’t come from her work — it came from her lack of workouts. “My health was suffering because I didn’t have my personal trainer with me,” she says.

So the Washingtonian set out to create an app that would allow users to carry their personal trainers in their pockets. The result is SweatSolo, now available in the iTunes store.

Trainers upload a schedule of workouts for their clients, who can use the app to pull up the exercises they’re supposed to be doing and mark each one when they’re finished. If a program is taking longer than it should, or not happening at all, it’s a sign something’s wrong. “They don’t need to raise their hands and say, ‘I need help.’ The trainer sees they’re missing workouts,” Clarke says.

To deter cheaters from merely phoning it in — and not actually doing the workout — the app also lists where the client is when an exercise is marked completed. “If the location is a bar in Chinatown, the trainer will say, ‘Let me pick up the phone’ and find out what’s going on,” Clarke says.

Over the past few months, SweatSolo conducted a pilot with D.C.-area trainers, including John Haley, who tested it with a client living in California. Without the app, he says, it would have been incredibly tricky to monitor her progress from across the country. “The time they’re not with you is always the hardest part,” says Haley, who even has trouble keeping local clients on track without regular appointments.

In the past, he’s written up lists of exercises, but a printout is much easier to forget than a phone, which his client was toting along to the gym anyway. “They’re using the devices to listen to music, and then they have the workout right there,” Haley says. More importantly, he feels like he’s right there, too. With the immediate feedback he’s getting, he’s been able to peek at her progress three times a week and adjust his schedule for her accordingly. “As a trainer, it gives me more work, but it allows me to do my job better,” he says.

But the app is better suited to motivation than instruction. “Form is the hardest part,” Haley says. Just because the assignments are completed doesn’t mean they’re necessarily being done correctly, and there’s nowhere in the app to insert detailed descriptions or videos. In the case of his California client, she’s a former athlete, and Haley trusts she understands how to follow his directions. But with less-experienced exercisers, he says it would be necessary to meet face to face at least some of the time.

That’s the point, says Clarke, who designed SweatSolo to serve as a supplement to in-person sessions, rather than as a substitute. The app has zero content unless a trainer has loaded it, and it’s there specifically for you.

So despite the name, if you’re using SweatSolo, you’re never really on your own.

How It Works

-Trainers register on Sweatsolo.com for an account that lets them set client schedules and see their progress. It’s $19.99 a month with a one-year contract.

-Clients download the SweatSolo app from iTunes for $3.99 (it will be available for Android and Blackberry devices soon). Their trainers can then send them workouts.