It used to be that Mom harped "Sit up straight!" when you slouched. Now there's a smartphone app with a belt that gives you a buzz if your posture slips.

Other apps send reminders — by e-mail, text message or pop-up, on-screen alerts — to take medications, go for a run, get an oil change or clean out the refrigerator.

As technology aims to help us solve all sorts of mundane problems, smartphones have morphed into digital nags. Repeated "suggestions" from a spouse can grate on the nerves, but users say it's easier — and less abrasive — to let a device issue the orders.

"I've set up an alert for my husband for garbage day," said Sara Swenson, of Cannon Falls, who uses the app Cozi to help keep her family on track. "It's about trying to get away from the nagging and make it be more of an electronic reminder that it's garbage day every Tuesday."

Such digital reminders are catching on. Evernote, an organization app that claims more than 50 million users worldwide, added pop-up reminders in May, saying they were one of the most requested features.

Yet it's unclear whether digital nagging is any more effective than the face-to-face kind. While devices may help us remember the little things, and be less likely to prompt eye rolls, the electronic alerts themselves can become overwhelming.

Stay on task

Greg Osterdyk gets five to 10 alerts on his smartphone each day, some from his calendar app, others from a task management app called Remember the Milk.

As mayor of Carver and a business owner, he's got a lot to remember.

"It's what enables me to handle more projects," he said. "I can't keep track of them in my head on my own."

He enters to-dos into the apps, and when the tasks are due, he gets an alert. "I had one today that was telling me there was an advertisement due to the newspaper," he said recently. "A couple others were calls I need to make, people I need to contact."

For such real-time reminders, a little digital nagging is probably helpful, said Dr. Sheila Jowsey, a psychiatrist at the Mayo Clinic. She's a particular fan of alerts sent by some airline apps that note updated flight information and gate changes.

But it is unclear whether nudges from a smartphone alone can alter more important behaviors, such as establishing a fitness routine or quitting smoking, she said.

"If you are significantly ambivalent and not quite ready to make that change, after a few reminders you'll deactivate it," Jowsey said. "It has to be something where you've come to the point in your own mind where you say, 'Ok, I'm ready for this.' "

Then there's the annoyance factor.

Being constantly interrupted, even by reminders that you programmed, can derail productivity, said Audrey Thomas, owner of Organized Audrey.

"If I'm focusing on something else and my phone is going off, then I lose focus on what I was working on," she said.

She recommends using technology for communication and organization, but turning off the alerts, especially for incoming e-mails, which she likens to needy toddlers.

"Toddlers come up to you and pull on your pant leg and they never stop until you give them your full attention," she said. "Put the nagging toddler in the playpen."

No eye roll necessary

Fans of digital alerts say that ability to turn them off is a key difference from human nagging.

"The nice thing about these reminders is that we, as individuals, can control them," said Mark Henderson, division chair for information technology at Mayo, who has been involved in developing its mobile app for patients, which includes a reminder features for upcoming appointments.

Technology can also be more consistent in its instruction and less emotional than a human.

Everybody has dealt with (and dished out) unrequested reminders, especially with family members. Researchers have found that repeated nagging can cause stress among couples, and even contribute to divorce.

"The digital delivery of something just cuts through all those innuendos, hidden meanings that sometimes are included in the spoken word but not in the pop-up text message that you get," Henderson said.

People interested in getting fit are often drawn to apps because the digital nudges offer accountability without any shame or blame, said Shannon Fable, director of exercise programming for Anytime Fitness. The Hastings-based chain of fitness centers offers apps and online tools for tracking workouts, including a feature that lets you schedule specific workouts in advance, and then send an e-mail reminder that day.

Other fitness apps, like MapMyRun, will send an alert if it's been awhile since the last jog. There are even wearable fitness gadgets like FitBit Flex and Jawbone Up that will buzz to remind people to get up and move at set intervals.

"Where a device is better than a person, it can be anonymous," Fable said. "It's not judging me. It might nag me, but I can turn it off if I hate it."

Indeed, Monisha Perkash, CEO and co-founder of posture app LumoBack, said some people turn to the buzzing belt and related app because the verbal reminders in their lives are getting to be too much.

"There are a lot of customers we have who do want their mothers or wives to stop nagging them," Perkash said. "This is a more gentle way."

Katie Humphrey • 612-673-4758