Chronos hands-on: Turn any watch into a smarter watch for $100

Many people have classic watches, heirloom watches, fashion watches, and other timepieces they prefer over today's smartwatches. Chronos provides some smartwatch functionality for just $100.
Written by Matthew Miller, Contributing Writer


For my 20th wedding anniversary, my wife presented me with a Citizen Eco-Drive Skyhawk Blue Angels watch. A few months later I started using smartwatches and only pulled out the Citizen for more formal events.

Studies show that people spend the majority of their time on an Apple Watch using the watch face (telling the time), managing notifications, tracking their activity, messaging with others, and interacting with Siri. The new Chronos smart disc provides the most used smartwatch functions and can be attached to the back of nearly any existing watch.


Last year after first seeing the Chronos disc, I immediately pre-ordered one. One year later we are now starting to see the Chronos ship out to those who pre-ordered the disc. My personal unit hasn't arrived yet, but Chronos sent along a media sample for me to evaluate in the meantime.

The Chronos ships in an attractive silver and blue retail package with the Chronos disc prominently displayed in a clear plastic area of the package. Inside you will find the Chronos disc, USB charging cradle, two-part cleaning swabs, and setup guide.

The Chronos disc looks like a large watch battery, made of stainless steel and plastic. It is shiny silver and only 3mm thick with a 33mm diameter. The Chronos disc weighs 10 grams.

Inside the Chronos you will find a Bluetooth 4.0 LE radio and 3-axis accelerometer. The Chronos has a reported two-day battery life and charges wirelessly when you place the disc into the included charging cradle.

Prior to attaching the Chronos to your watch, you clean the back surface of your watch with the two included wipes. Remove the plastic protective cover from the back of the Chronos and then attach the Chronos to the back of your watch. The Chronos attaches via a non-residue microsuction material.

There are four LEDs along the edges of the Chronos disc. The Chronos also has a vibration motor inside that you can feel in different patterns on the back of your watch.

Hands-on with the Chronos disc: in pictures

My Citizen watch is water resistant to 200 meters. The Chronos disc has a water and dust resistant rating of IP67. So while you can't take it swimming, you don't have to worry about sweat or rain ruining the Chronos disc.


The Chronos disc connects to your smartphone via Bluetooth. At launch, there is an iOS app with an Android app coming soon. I've been testing the Chronos with my Citizen watch and Apple iPhone 7 Plus.

After installing the app, a setup procedure is initiated that pairs your Chronos and also asks if you wish to connect to Apple Health. The Android app will likely connect to Google Fit.

The Chronos disc functions as a basic activity tracker with the ability to provide notifications and gesture controls. These functions are controlled through the Chronos app on your smartphone. At the bottom of the app you will find icon buttons for fitness, notifications, and gestures.

Fitness: Tap the word manage on the center of the fitness circle to set your step, distance, and active calorie goals. While on the fitness tab, swipe from right to left and back again to view step, distance, and active calorie status.

Notifications: You can add app and contact notifications to your Chronos on the notifications tab. App notifications can be setup for calendar, email, Facebook, Google+, Instagram, Twitter, Uber, Whatsapp, Facebook Messenger, Messages, Phone, and Snapchat. You can also setup notifications for specific people in your contacts list.

After selecting an app or a contact, you then have the option to select from seven LED light colors or no light and one of three vibration patterns. When you select the light and vibration pattern, the light and vibration will occur on your Chronos to confirm your selection.

Gestures: When I pre-ordered my Chronos last year, I figured it would provide me with light and vibration functons. I was surprised to see there are additional gesture controls available, making the Chronos more valuable.

With iOS, you can use gestures to silence incoming calls, function as a camera remote to take a photo, control media playback, and find your phone. Gestures include multiple taps on the watch face or side of your watch.

There is also a left menu in the app so that you can find your Chronos or turn on a 10-second light to view the lights. The battery status of your Chronos is also shown on the left menu.


Setup of the Chronos was quick and easy. After attaching it to my watch, I then popped it onto the wireless charging cradle and fully charged the Chronos. It charges quickly, but since I never sleep with my watch I just set it on the cradle in the evening. There is no sleep tracking functionality in the Chronos so there is no reason to wear it to bed.

The Chronos is thin and light and after a few days of wear, I never noticed it affecting the feel of the watch on my wrist. The Citizen Eco-Drive was already a rather heavy big watch and 10 grams of weight with 3mm of additional depth didn't change it much.

After a few days of use, I'm not yet reaching a two-day battery life. However, I have no problem going a full 18-hour day with the Chronos tracking my activity and notifying me through several apps.

The vibration has been strong enough to alert me when a notification is activated and the lights allow me to quickly glance down to see which person or app is activated. It would be nice to be able to customize the vibration patterns beyond the three default options.

The gesture controls work well and I especially find the camera remote useful for taking photos. This is one activity I use with my Apple Watch.

I chose to have my activity synced to Apple Health, but am seeing odd behavior with the step counts. It seems that the Chronos is showing me double the amount of actual steps taken, which may have something to do with the sync setup. When I go into the Apple Health app and view the raw data, the number of steps recorded closely matches the typical steps I take daily and have recorded on other apps. I'll pass my experiences along to Chronos and hope they can fix the software to prevent this double counting.

Without the ability to sync to an external app, the view of your fitness data is not very useful in the Chronos app. It shows colored lines on the circle for times when you were active, but you can only view daily steps, distance, and calories. I would expect to view the data by weeks and months too.

The Chronos is a fairly simple device, but it adds the most popular smartwatch functions to any watch you currently own. This can save you hundreds of dollars, and if you have an expensive watch you like then it could save even more compared to an expensive Apple Watch. The Chronos disc is a solid option for those who are curious if they would ever use a smartwatch and is less expensive than nearly every smartwatch available today.

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