Alara for iPhone (free with optional in-app donation) lets you monitor each day's UV index, which is the "expected risk of overexposure to UV radiation from the sun." The US EPA notes that one American dies of skin cancer every hour, and that "unprotected exposure to UV radiation is the most preventable risk factor for skin cancer." It was this very fact that drove developer Lee Morgan to develop Alara:
"A few years ago a friend of mine, whom I served with in the Air Force, was diagnosed with Melanoma. Upon his diagnosis he was medically discharged from service. I won’t go into the details but suffice to say dealing with melanoma has been very difficult for him and his family."
Morgan notes that he and his wife are light-skinned, increasing their susceptibility to melanoma. Not being able to find an app that suited their needs, he built one of his own. Alara is the result.
The way it works couldn't be simpler. When launched, Alara notes your location and grabs local UV index information from the EPA’s public service, Envirofacts. Note that the only data that is transmitted to the EPA is the current location's zip code. No personal information is shared, and the location is only specific enough to get accurate UV index measurements.
Data is displayed in an hour-by-hour bar graph. The UV index is a scale from zero to 11, and the bars get taller and change color as the risk increases. Also, you can tap any bar to get detailed information about its score. For example, an index of seven reads, "High. Protection against sun damage is needed. Wear a shirt, hat and sunscreen SPF 30+." Finally, the current index number description and prediction for the next hour ("falling," for example) is displayed front-and-center.
Everything is clear and legible. Alara is free, and a "tip jar" button in the upper right gives you the option of sending Lee $0.99, $1.99 or $4.99 for his efforts and the continued development of Alara.
Alara 1.1, now available in the App Store, supports VoiceOver for those with visual impairments. Morgan wrote a great post about the process he went through when bringing accessibility to his app.
As a freckled, light-skinned bald man who had a bit of skin cancer removed about five years ago, I'm all for Alara (and I have a very large collection of hats). It's easy to think, "I'm out in the sun but I didn't get burned so I'm good." That's not necessarily true. Use an app like Alara to help keep yourself and you loved ones safe while enjoying the great outdoors.