We've all been told that 7 to 9 hours of sleep is healthy, but recent studies are showing that quality of sleep is more important than quantity. If you sleep 8 hours every night but still feel terrible in the morning, this might be why -- and you aren't alone.

According to The National Sleep Foundation, 35 percent of Americans describe their sleep quality as "poor" or "only fair", which are correlated with high stress and low life satisfaction. For a happier life, you don't need to sleep more. You need to sleep better.

Which is why sleep gadgets are on the rise, and users are reporting great results all around. Here are 9 of the best that we've found. You don't need all of them! Even one can do wonders, as long as you pick the one that best fits your lifestyle and needs.

1. ResMed S+ Sleep Sensor ($130)

The ResMed S+ Sleep Sensor is a no-contact device that sits on your nightstand. Just point it towards you and it will track your body movements and your breathing patterns as you sleep. Based on this information, it generates a "sleep score" that shows how well you slept.

But it also tracks outside factors, such as room temperature, light levels, and noise levels. Over time it will try to provide personalized feedback, and you can use this information to pinpoint and address reasons why you might be getting subpar sleep.

The ResMed S+ synchronizes with your smartphone or tablet, making it easy to view all of its data and settings through a simple mobile app.

2. Beddit 3 Sleep Monitor ($150)

The Beddit 3 Sleep Monitor is a thin, flat sensor that slips underneath your bed sheets so you're resting on top of it. It's wide enough to track 1 or 2 people and soft enough that you won't even know it's there. It starts tracking automatically as soon as you get into bed.

Tracking consists of snoring awareness, tossing and turning, and sensors for temperature, humidity, heart rate, and breath rate. Its data are synchronized to your smartphone or tablet, where you can view your sleeping patterns, including both quality and quantity of sleep.

3. Fitbit One Wireless Tracker ($100)

If you want to track sleep but don't want to clutter your nightstand or insert anything into your bed, then the Fitbit One might be right for you. It's an activity tracker that you can wear anywhere -- unlike other wrist-worn Fitbits, the One is a clip-on device.

It isn't just a sleep tracker, though. In addition to monitoring how long and how well you sleep, not to mention its silent wake-up alarm, it also tracks steps taken, elevation changed, distance moved, and calories burned.

4. Muse Brain-Sensing Headband ($200)

The Muse Brain-Sensing Headband is a wearable headband that helps you relax by measuring your brain signals to determine if your mind is calm or active.

It's most useful when you pair the headband with your smartphone (through the Muse app) and wear earbuds at the same time. The app adjusts to your current brain activity and helps guide you towards calmness.

Using the Muse to quiet your mind before bedtime helps you fall asleep much faster, but it can also be used throughout the day for destressing, relaxation, and meditation.

5. Hush Smart Earplugs [No Longer Available]

The Hush Smart Earplugs are basically wireless earbuds that you wear while you sleep. The foam cushions block out noise to help you fall asleep and stay asleep, and the earbuds themselves generate soothing sounds to calm your mind.

As of this writing, production has been put on hold because the company has "something new in the works." We don't know how long the pause will last, but you can stay up to date by subscribing to the Hush newsletter. The Hush originally retailed for $150.

6. Glo to Sleep Smart Mask ($150)

Sleep masks are plenty useful already, but the Glo to Sleep Smart Mask cranks it up a few levels. In addition to blocking ambient light, it has a built-in screen that encourages sleep with warm-colored light and nudges you awake with pulses of cool-colored light.

Note that it can also be used for refreshing power naps! If the price tag is too steep, you might consider getting the simpler Glo to Sleep Therapy Mask for $40. Instead of the active lighting method in the smart mask, this one is more passive.

Or if you'd rather not spend anything at all, you can install blue light filter apps on all of your smartphones, tablets, and computers to simulate this effect to a lesser degree.

7. Smart Nora ($300)

Did you know that snoring isn't just a nuisance for those around you? Snoring is caused by an obstruction in your airway and is the sound of air forcing its way to your lungs. Snoring can also be a sign of sleep apnea, which can be dangerous if kept unchecked.

Smart Nora promises to reduce snoring in just two weeks. The makers are so confident that they've backed it with a 100 percent money-back guarantee.

Simply put the Nora expander inside your pillow. When the Nora receiver detects snoring, the expander either inflates or deflates. The gentle moving of your head opens up your airway so you can breathe more freely, all without waking up.

8. Philips Wake-Up Light ($50)

Say goodbye to alarm clocks. Jolting yourself awake with loud noises is not the best way to start the morning, especially if the alarm goes off mid-deep-sleep and leaves you groggy all day.

The Philips Wake-Up Light is a bedside lamp that mimics a natural sunrise by slowly growing brighter and brighter as your wake-up time approaches. At night, it can be used as a normal lamp with 10 different light intensity settings.

Light plays an important role, not just in waking up but in overall mental health. Being cooped up inside all day can lead to light deficiency, which can further lead to seasonal affective disorder and even chronic depression. Fortunately, light therapy lamps can help!

9. Sleep Number it Bed ($650+)

Okay, a bed may not be a gadget per se... but if you're having sleep problems, then you should absolutely assess your bed to make sure it isn't the root cause. A poor-quality mattress can negate even the coolest and most sophisticated sleep gadgets.

The it Bed by Sleep Number is a smart bed (8-inch mattress included) that can be controlled by your smartphone or tablet using Bluetooth. It tracks your sleep quality by monitoring things like heart rate, breath rate, and room temperature, then adjusts accordingly.

It's available in Twin, Twin Long, Full, Queen, and King sizes. For Queen and King, each side is monitored separately and allows for sleep tracking of 2 people.

More Tips for a Better Night's Rest

There are two more factors you shouldn't overlook when it comes to sleep.

  1. Temperature. Neither too cold nor too hot because both will wake you up throughout the night and ruin sleep quality. The National Sleep Foundation recommends a room temperature of 65 degrees Fahrenheit.
  2. Humidity. If there isn't enough humidity in the room, your skin and sinuses will dry out. This can cause sore throats, stuffy noses, and coughing. Too much humidity can make the room feel hotter and encourage mold growth.

We highly recommend using a Nest Smart Thermostat to maintain a comfortable temperature (while slashing your energy bill in the process) and a hygrometer like the ThermoPro T55 or AcuRite 01083M for measuring indoor humidity.

Which do you have most trouble with: falling asleep, staying asleep, or waking up? What other tips and tricks have you picked up that have proven helpful? Share with us below!