What is My Skin Track UV?

My Skin Track UV by La Roche-Posay is the first battery-free wearable electronic sensor to monitor personal UV exposure. The personalized technology provides updates in real-time, stores up to three months of data and shows exposure trends over time. My Skin Track UV and its accompanying app make personal UV data easily accessible, allowing users to track their UV exposure—as well as humidity, pollen and pollution levels—and get customized skincare recommendation based on their skin concerns.


How does the sensor work?

The battery-free sensor is activated by the sun and powered by the user’s smartphone using near-field communication. My Skin Track UV relays stored data to its accompanying app through an easy single-touch function: users simply tap My Skin Track UV against their smartphone to update the app.


Why doesn’t the sensor need a battery?

The battery-free sensor is activated by the sun and powered by the user’s smartphone using near-field communication. Near-field communication is a method of close-range wireless data transfer that allows two devices to exchange data without the need for an internet connection. NFC-equipped smartphones and other devices can exchange information with each other with an easy wave or tap.

How do I turn the sensor on/off?

The sensor does not need to be turned on or off because it is battery-free. You can start using it at any time. And even if you don’t use it for a prolonged amount of time, it will not impact its quality.

How long will the sensor last?

Because the sensor is battery-free it can last for years as long as it is well taken care of.

How do I charge the sensor?

There is no need to charge the sensor because it is battery-free.

What types of phones is the sensor compatible with?

The sensor is compatible with NFC-enabled smartphones. iPhone 7 and later versions are all NFC-enabled. Most Android phones since 2015 are also NFC-enabled.

How do I know if my phone is NFC-enabled?

iPhone 7 and later versions are all NFC-enabled. Most Android phones since 2015 are also NFC-enabled. If you’re not sure, check the specifications of your phone online. There are also free apps that allow to test your phone to determine if it is NFC-enabled.

Will the sensor ever be compatible with older models of phones?

No – the sensor can only work with NFC-enabled phones which are relatively recent phone models. Older phones cannot be updated to be NFC-enabled so the sensor will not work with them.

My phone is not NFC-enabled. Can I use the sensor any other way?

No, the sensor is only compatible with NFC-enabled phones.

Does the sensor work on tablets?

No, the sensor only works with NFC-enabled smartphones – therefore the My Skin Track UV app is only developed for smartphones, not tablets. Currently, most tablets on the market are not NFC-enabled.

Does the sensor work on the Apple watch?

While the app integrates seamlessly with Apple’s HealthKit, it does not sync with the Apple watch as it is not equipped with NFC technology.


When and how frequently should I scan the sensor?

You can scan the sensor as often as you’d like. We recommend scanning at least twice a day: at the beginning of the day and at the end. If you are outdoors, it is recommended to scan at least every two hours. 

Can multiple people use the same sensor?

Multiple users cannot simultaneously use the same sensor, however multiple users can use the sensor at alternating times. Before giving the sensor to someone else to use, scan the sensor with your phone using the My Skin Track UV app to empty the sensor memory and download the stored data to your phone. The next user will have to create his/her own profile, entering information about skin tone, skin type and skin concerns.

How do I scan the sensor with my phone?

When in the My Skin Track UV app, tap the sensor icon on the top right corner of the home screen. This will open a pop-up on your screen prompting you to scan your sensor. Place the sensor in direct contact with your phone, on the area of your phone where the NFC reader is located. If you’re unsure where the NFC reader on your phone is located, check your profile on the My Skin Track UV app. You can select the model of your phone in the NFC Reader Location section and the app will indicate where the NFC reader is located.

Can I scan the sensor with a case on my phone?

Most phone cases won’t interfere with scanning, but if you are having trouble getting a read, try removing your case. Occasionally, the material or the thickness of the case might inhibit scanning. 

How and where should I wear the sensor?

Snap the circular sensor into the enclosed metal clip. The clip can then be easily attached to your clothes and accessories. Make sure that the sensor is facing outwards while wearing it to ensure it is getting exposed to light.

How do I know if the sensor if working or not?

There is no power indicator on the sensor because it is always on. If you’re wondering if it is working properly, simply open the My Skin Track UV app and scan the sensor with your phone. A functioning sensor will sync with the app, you will only receive a notification if the app is unable to successfully read the sensor.

Can I put sunscreen on my sensor?

No you should not put sunscreen on your sensor.

Does the sensor work if it is covered? Can I put my sensor under my clothes?

For accurate results, the sensor must be uncovered and exposed to light to measure your UV exposure most accurately. If covered, the measurement might not reflect the actual amount of UV exposure your skin has received.

Does the sensor work indoors?

Yes the sensor works both indoors and outdoors.

Will the sensor alert me before I get a sunburn?

The companion app will alert you when the UV index is high or when your percentage of max-sunstock is high based on your location, your skin-type and your collective time in the sun.  However the sensor cannot predict or prevent sunburn. The higher the UV index and the higher your percentage of max-sunstock, the higher the risk of overexposure to the sun.  Some key sun safety tips include: regularly using a sunscreen with broad spectrum SPF value of 15 or above, limiting time in the sun, especially from 10am to 2pm, and wearing long-sleeved shirts, pants, hats and sunglasses.

What is the size of My Skin Track UV?

The discreet wearable sensor is 12mm wide and 6mm high, and weighs 17.4 grams, including the clip.


Is it safe for children to use the sensor?

Yes, however because of the senor’s small size, we recommend that it only be used for children ages three and up.

Is the sensor resistant to water and liquids – can I swim with it?

The sensor is IP67 resistant which means it can resist water for up to 30 minutes if immersed in 3 feet of water or less.

Will the sensor work if I accidentally left it on my clothes in the washing machine?

The sensor may stop working if immersed in water for more than 30 minutes. To verify if your sensor still works, use the My Skin Track UV app and try to scan your sensor.

What is the sensor’s return policy?

Please verify the return policy of Apple.



What information does the app provide?

The app provides user-friendly, customized data about the wearer’s personal UV exposure and provides additional information including UV index, weather, air quality, pollen, and humidity. The user can input personal information including their skin concerns and the app provides skincare tips and product recommendation as well as notifications when environmental factors reach levels that may have an impact on skin.


Where can I download the app?

The My Skin Track UV app can be found in the App store and on Google Play.


Can I use the app without the sensor?

The sensor is needed to measure your personal exposure to UV and to receive alerts. However, without the sensor, you are still able to access partial information based on your location, such as weather and temperature.

What does max-sunstock mean?

Your "max-sunstock” is a customized value representing the maximum amount of UV rays your skin may be exposed to before being considered at higher risk, according to a scientific review by a team of scientists and dermatologists.. This value takes the information you provided about your skin tone into account along with the UV index. Dermatologists recommend wearing sunscreen daily, even when UV exposure is low: wear sunscreen, reapply regularly and limit time in the sun.

What does the percent of max-sunstock mean?

The percent of max-sunstock is an indication of the amount of UV you’ve been exposed to in relation to your calculated personal max-sunstock.  Essentially it is a gauge of your personal UV consumption and level of risk.  

Do I need to wear sunscreen if I’m not reaching 100% of max-sunstock?

We recommend using sunscreen daily, even if your percent of max-sunstock is under 100%. Even low doses of UV exposure can be detrimental for your skin. To help prevent sunburn and help decrease the risk of skin cancer and early skin aging, regularly use a sunscreen with broad spectrum SPF value of 15 or above and take other sun protection measures including limiting time in the sun, especially from 10am to 2pm and wearing long-sleeved shirts, pants, hats and sunglasses. Make sure to reapply frequently as detailed in the directions of your sunscreen.

Why is my percent of max-sunstock not decreasing after I applied sunscreen?

Your sensor measures UV exposure independently of whether or not you applied sunscreen. It is an indicator of the level of UV rays that you have been exposed to.

Why is my percent of max-sunstock increasing although I wasn’t in the sun most of the day?

Even when not directly in the sun, UV rays can still reach your skin

Does the app measure both UVA and UVB rays?

The sensor and its companion app measure both UVA and UVB rays.


What is the difference between UVA and UVB rays?

Your sensor measures two types of UV rays: UVA and UVB rays. UVA and UVB rays are present all year round, but UVB rays are particularly high in the summer and at midday. UVB rays are a leading cause of sunburn and increase the risk of skin cancer. UVB do not go through glass and are partially blocked by clouds.


UVA rays are present all year round, regardless of how hot or sunny it feels. UVA rays are a leading cause of early skin aging and increase the risk of skin cancer. UVA rays can go through glass and clouds.


Why is the app asking what my skin tone is?

Your skin tone is an important data point for our algorithm to calculate your max-sunstock most accurately. By providing information about your skin, you will receive the most accurate readings.

What operating systems is the app compatible with?

The app is compatible with iOS 11 and up and with Android version 7 and up.  

Why is some of the data such as temperature, humidity or air quality different between the app and my weather app?

Several data points in the My Skin Track UV app are pulled based on your exact localization. Many weather apps are based more broadly on the city in which you are located and may therefore provide data that is less customized.

What is the difference between this app and other available apps that measure UV, pollution and other environmental factors?

You can use other available apps to be informed about various environmental factors, however, only the My Skin Track UV sensor and companion app will provide you with a personalized reading of your UV exposure and provide notifications and advice when environmental factors are at a level that may have adverse effects on your skin.

Why is the app suggesting to connect with my Apple Health Kit?

Connecting with the Apple Health Kit is optional. If enabled, it will allow data such as the UV index to be pulled into the Apple Health Kit ecosystem, where other personal data like activities and health records can also be housed.

Is the data in the app accurate if I didn’t have my phone with me all day?

Yes, the data will be accurate as long as you wear the sensor. You will only be able to access the data by syncing the sensor with the app on your phone.

How does air quality impact my skin?

High levels of pollution have been shown to adversely affect very dry/eczema-prone skin, oily/acne-prone skin, sensitive skin, or skin with visible dark spots.

What is the “Activities” tab?

The “Activities” tab allows you to log activities such as tennis and running. Logging an activity allows the algorithm to gauge a highly accurate reading of your UV exposure, allowing you to track  how your activities are affecting your exposure to UV and other environmental factors.

How do I log in an activity?

Use the “Activities” tab, at the bottom of the My Skin Track UV app. Click on “Start New” and select the type of activity you’re about to begin. Before starting the activity, select “Tap & Scan to Start”. This action will prompt you to scan your sensor. You can press the pause button in the same tab at any time as needed. Once you’ve completed the activity, press the stop button, at which point you will be prompted to again scan your sensor. This allows you to get accurate readings of UV exposure during specific activities.

What is the “Skin Advice” tab?

This tab provides you with a personalized skincare regimen of La Roche-Posay products, based on your skin type and the skin concerns you have entered in your profile.