We’re in a golden age of arguably unnecessary health gadgets, including several new entries to the market that aim to optimize our sleep, or at least give us lots of data describing it. We asked a few sleep experts what’s useful and what isn’t.

Anything That Reminds You Sleep Is Important

“The best thing [sleep tech does] is bringing to people’s attention that sleep is important and you should be aware of your sleep,” says Dr. Sara Benjamin from the Johns Hopkins Center for Sleep.

She and another sleep expert we spoke to, Dr. Chris Winter of Charlottesville Neurology and Sleep Medicine, liked the idea behind the free Shleep app that gives you little tips and lessons on how to get better sleep. (Neither had time to check out every tip in the app, but both said that what they saw looked like reasonable advice.)

“Everything related to sleep is pretty easy on the surface,” says Dr. Winter, since the message most of us need to hear is just to get our butts into bed on time. “But sometimes you have to see it in different formats or hear it in different ways to get it to stick.”

I clicked through Shleep’s quiz about sleep habits, making my best guess about how many hours I sleep on weekends and weeknights, and admitting that I sometimes use my phone in bed. The app then started me on a ten-day course of lessons, guided by a cartoon sheep, about ways to keep my phone from distracting me late at night.

A Reality Check on How Much Sleep You’re Getting

Neither of our experts put much stock in sleep trackers’ breakdown of what kind of sleep you’re getting during the night. “A fitness tracker might overgeneralize light sleep,” says Dr. Benjamin, leading her patients to think they’re not sleeping well when actually they’re spending much of the night in N2 sleep, which is perfectly normal.

Medications and aging can also affect your stages of sleep, she points out, so there’s not a single perfect sleep architecture everyone can aim for.

But any sleep tracking gadget—whether it’s an under-the-bed pad, a headband, or a microphone that sits by your bed and listens to you breathe—should be able to give you a pretty good sense of when you’re sleeping. “The nice thing about a [sleep tracker] is that it’s a truth teller,” says Dr. Winter. You might think you’re getting plenty of sleep, but if the app tells you that you’ve been up late every night this week, you know what you need to do.

The data from a sleep tracker can also help to start a conversation with a professional if you decide to seek help, but once again your total amount of sleep is likely to be one of the more relevant numbers. “If you’ve got severe sleep apnea and you’re getting 10 hours of sleep but it’s not restorative, you need to get that apnea treated,” says Dr. Benjamin.

Smart Alarms

I was skeptical that smart alarms—ones that say they can wake you at just the right point in your sleep cycle—are all that useful, but both our experts said they make sense. “People generally feel kind of cruddy if they wake up during REM sleep,” says Dr. Winter. Your body is paralyzed during that stage, so a gadget can wait for you to stir a little before it wakes you up.

It also helps your partner’s sleep if your alarm is something that can wake you up without disrupting the person sleeping next to you.

But Maybe You’ll Sleep Better With Less Tech

Getting a pile of data doesn’t help if you don’t know what to do with it. Dr. Winter, who has consulted for sleep tech companies, is optimistic that soon sleep gadgets may be able to offer more interpretation of what’s going wrong with your sleep and flag things that might be problems you should discuss with a doctor. But if we’re just getting a lot of data on our sleep without any explanation of what’s going on, he says, then all the app or gadget is doing is helping us “admire our problems.”

Neither expert wanted to completely discount the sleep gadgets we talked about, so if a $400 headband helps you sleep, there’s probably nothing wrong with using it. None of the new gadgets have much data to back up their effectiveness, though, so you really are on your own for figuring out whether you’re actually going to get $400 worth of good sleep out of it.

Sometimes what you need isn’t more tech at all, though. Like the Shleep app has been telling me, fiddling with screens or blinky lights at night is not a sleep-friendly activity. Dr. Winter says there’s a danger to obsessing over “flashier, sexier” products that promise to fix your sleep, instead of simple actions that you’re overlooking—like getting more sunlight in the morning or buying yourself a more comfortable pillow.

This content was originally published here.