Spoiler alert: Even on cool summer days, you still need to layer on sunscreen to avoid ending up with a red-hot burn. Ultraviolet (UV) radiation levels, which cause sunburn, can still harm you even if it isn’t sunny and warm outside. There’s no correlation between UV levels and temperature, so the sun’s rays can singe you during both winter and summer! And though laying out on the beach may feel great, excessive UV exposure can lead to cataracts, premature skin aging, sunburn and skin cancer, which is the most commonly diagnosed cancer in the United States. If you spend time outside during any season, it’s important to know when your skin is most at risk for sun damage.
Fortunately, there’s an app for that. New smartphone tools can provide detailed predictions on what times of day are most dangerous to be outside, based on the UV index. A scale from zero (least dangerous) to 11 (most dangerous), UV index is calculated by accounting for sunlight angle, forecasted cloud cover, elevation and ozone throughout the day.
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Use these apps to figure out when you are most vulnerable to burning. Plus, we’ve got one that will help you monitor your moles just in case you already spent a little too much time outside.
Cool Apps for UV Index and Skin Safety
1. Wolfram Sun Exposure Reference App
Based on your skin type, what SPF you’re wearing and the UV forecast for your location, this comprehensive app can predict exactly how long you can stay in the sun before burning. Organizing a trip to the shore? Check out a five-day UV forecast displayed on a map, and find out what hours each day you should minimize sun exposure. ($0.99; available for iOS)
2. Ultraviolet ~ UV Index
Keep things simple with this cool tracker, which displays the current UV index in your area using a large, vibrantly colored circle. Blues and greens mean you’re in the clear while reds and purples mean a dangerously high index. General sun safety advice will tip you off for when it’s time to put on a hat, apply sunscreen or avoid going outside altogether. Just the bare necessities for when you’re bare at the beach. (Free; available for iOS)
3. EPA’s SunWise UV Index
The U.S. Environmental Protection Agency designed this easy-to-navigate application, which delivers location-based UV index information. Ideal for plan-ahead types, the most useful feature is the color-coded hourly forecast that makes it easy to spot when the UV index is highest. (Free; available for iOS and Android)
Heading to the beach or a tanning bed to bronze is never a good idea. Instead of using this app to tan, repurpose it to help you be smarter about sun exposure. TANtastic gives a five-day UV index and weather forecast, including temperature, wind, humidity and chance of rain. Keep your sun minutes to a minimum by using the tool’s timer to remind you when to reapply sunscreen or seek shade. (Free; available for iOS)
5. Doctor Mole – Skin Cancer App
Even SPF junkies need to monitor their moles for changes. If you’ve had at least five sunburns, your risk for melanoma will double, according to the Skin Cancer Foundation. Though moles can be benign, it’s essential to monitor the size and shape of the small brown spots on your body in case they do become cancerous. Enter Doctor Mole, an app that assesses your moles’ border, color and diameter. There’s an archive for images so you can determine if and how your moles are changing and whether it’s time to see a health care professional. ($4.99; available for iOS and Android)
Originally posted on August 4, 2014. Updated on May 2015.