When you’re not using your smartphone for playing Angry Birds, text messaging and tweeting random thoughts, you can use it to help fight off creepy-crawlies. “The Facts of Lice,” a free iPhone app developed by Fairy Tales Hair Care, compiles tips that will help keep the little bloodsuckers from making their home in the scalp of someone you love.

Forget curriculum reform, teachers unions and cheating scandals. For many of the nation’s parents, the biggest worry at the start of a new school year comes from a much tinier source: head lice. School officials and medical professionals say the parasitic insects are a top fear for families with school-age children...