Mobile Warming Bluetooth-enabled Primer baselayer shirt review: Staying toasty warm in freezing temperatures

"There's no such thing as bad weather, only bad clothes", someone once said. But when temperatures drop and we're stuck on a ski lift, cold temperatures can easily creep into even our best-insulated clothing. Once you're cold, it's no fun to play in the snow. I've recently had the chance to test out the Primer Shirt baselayer by Mobile Warming 'Technology by Fieldsheer'.

What makes this long sleeve shirt unique and worth talking about is that it comes with an integrated Far-Infrared heating system with a 7.4 volts battery, providing all-day comfort in the freezing cold weather. With Bluetooth-enabled, built-in touch control buttons, the shirt is on the cutting edge of bringing together clothing and technology.

Here is how the Mobile Warming Primer baselayer shirt works

Primer Shirt baselayer by Mobile Warming

The shirt has sewn-in heating elements in the front, over the chest, and on the back over the shoulders. On the bottom right is a button that lets you adjust the heat, based on your need and outside temperature. The button is easily accessible and sits right next to a little pouch, which stores a battery back that can be unplugged whenever you need to recharge the battery.

The one-touch button works pretty simple and lets you easily cycle through the four different heat settings. For each setting, the button illuminates in a different color, which is very smart. To add even more convenience, the shirt can be connected via Bluetooth 4.0 for low battery consumption, to a slick app on your iPhone or Android device. The app allows you to control the heat output and check the battery level. Yes, you read that right, a Bluetooth enabled shirt! The app is super useful, allowing you to control the heat output and to manage the battery performance when you're out in the wild and want to make sure you're not running out of juice. The higher the heat output, the shorter the battery life.

When wearing the shirt you barely notice that you're wearing a battery pack and wires. Your movement doesn't feel limited in any way, and everything is lightweight, sewn-in nicely, and stowed away. The shirt is made with a moisture-wicking mesh liner and feels like a great performance baselayer. The temperature can be controlled to your liking, giving you a toasty warm feeling or just a little bit of warmth if you want to keep it on for a long day on the slopes. Their marketing material promises between 2.5 and 10 hours of battery life.

The app itself is really well designed. It just focuses on the basics and doesn't confuse you with too many preferences. If you have multiple Mobile Warming items, like gloves and a shirt, or a vest for your dog (yes, those exist, too). You can easily connect each one to the app, give each garment a unique identifier, and manage them all. Of all the Bluetooth-connected devices I own, this one works the most flawlessly with my iPhone.

You can wash all of these products, which is of course necessary. But you can't put them in the dryer, and you have to remember to take out the battery before washing. The Mobile Warming online store sells replacement batteries and chargers, just in case you accidentally ruin one by washing it.

Mobile Warming Primer baselayer shirt: What I like

Cross-country skiing

  • Intuitive setup - out of the box easy to use.
  • Works flawlessly - Bluetooth connection works.
  • Great mobile app - simple app, allows you to control multiple warming products on screen.
  • Simple one-touch button operation - even without the app, the button on the side of the shirt is easy to use, even while wearing gloves.
  • Low-profile construction - you barely notice wearing technology and your movement is not restricted.

Mobile Warming Primer baselayer shirt: What I don't like

(I'm reaching here because I really like the product)

  • Price - $160 is a lot to spend on an undershirt
  • Limited colors - It only comes in gray

Mobile Warming Primer baselayer shirt: Bottomline

Cross country skiing

For winter outdoor activities in cold climates, like skiing, hunting, hiking, snowmobiling or any other activity that doesn't give you a ton of aerobic output, the Mobile Warming products offer a pretty simple and effective solution to keeping you toasty warm. The baselayer costs between $35 and $160, which is not cheap for a performance long sleeve shirt, but the built-in tech works so well, that it's actually a joy to use and makes the price point worth it.

Take care of the product as you would with any tech product, and the cold winter days on exposed ski lifts will never bother you again. Other products in their lineup include gloves, jackets, pants and even vests to keep your dog toasty warm.

Mathias Eichler

Mathias creates beautiful many things. Co-founder of the Outdoor Society, publisher of outdoor inspiration including guidebooks, calendars and the weekly trail running podcast Singletrack. In his spare time he runs trails and climbs the mountains around his base camp Olympia, WA. Find him at The Outdoor Society or @mathiaseichler.