BullGuard Mobile Security 10 ($29.95; Android; BlackBerry; Symbian; Windows Mobile) provides antivirus protection for your phone and can wipe data from a lost device.
Fan of street food? The Eat St. app (free; iPhone, iPod Touch) plots food carts—many with profiles that include their Twitter feed, menu, and hours—in 318 cities in the U.S.
Worried your checked bag might be over the airline’s weight limit? Balanzza’s Mini Luggage Scale ($24.95) is compact, handheld, and can weigh objects of up to 100 pounds.
Keep track of the flight departures and arrivals of 1,400 airlines at more than 4,000 airports around the world with Mobiata’s Flightboard app ($3.99; Android; iPhone, iPad).