Spire review: Every breath you take, Spire will be watching you
Spire is a small device that you clip on your belt or bra, and it detects your inhalations and exhalations. This data gets sent to your iOS device, which provides insights into how you breathe.
The app records three types of breathing: calm, focus, and tension. Your breath affects your body and your mind, and your mind affects your breathing. Understanding how breathing and stress are related helps you take control of your stress more efficiently.
When you're calm, your breathing is slow and smooth; when you're focused, your breathing is a bit faster, but regular. And tension is reflected by rapid, irregular breathing. Spire records this information, and shows you "streaks," or periods when your breathing matches one of those three types.
Spire is mostly retrospective. While you can view information in its app about your current breathing status--whether you're in a streak or not--it's more designed to look back on your day and see how it went. As such, its information is a bit limited. However, you can set up notifications on your iPhone or Apple Watch to tell you, for example, when you're tense, when you haven't taken a deep breath in a certain amount of time, and more. The Spire device can buzz for notifications, which is fine to alert you that you should take a deep breath, but I don't find it useful to have it buzz to tell me that I'm calm.
Spire also offers guided breathing exercises and meditations, called Boosts. You can download these and listen to them to calm down, enhance focus, and more.
Spire also counts steps, and estimates calorie burn, but it's not as sophisticated for these features as a real fitness tracker. However, if all you care about are the basics of your activity, it's accurate enough for that purpose.
Spire's battery lasts about four to seven days, and uses Qi charging: there's no cable to plug in, and you simply place it on a charging plate. When the device's battery gets low, you get a notification, and it charges in about two hours.
The Spire app displays a message, when you launch it, saying "Spire can't track your day if you close the app." This does not mean that the app has to be open and visible; it simply has to be running. Spire's team told me that many users actually force quit apps on iOS regularly, which leads to the device not being able to track at all. The Spire app uses a fair amount of your battery. In my tests, on an iPhone 5s, it burns about 15 to 20 percent of my battery, even without my checking the app often.
I think Spire is a great idea, and one that has been missing from wearables until now. I'd like to see it offer more actionable data, however. For example, it could link to events in my calendar to tell me that I'm tense every time I have a meeting with a specific person. Or it could use the GPS on my iPhone to show me where I was when I was tense, or when I was relaxed. I think it would be great if it included a sort of biofeedback feature to help you calm down, based on your breathing, such as the $4 Breathing Zone app offers. Spire's team told me that they're planning to integrate lots of new features to the device in the future.
Bottom line
Spire is a unique tool for monitoring one part of your health that other wearables ignore. By monitoring your breathing, Spire can help you better manage your stress levels.