Colleges and universities are teaming up with technology entrepreneurs in an effort to keep students safe — on and off campus — by using their smartphones. Mobile apps geared toward campus safety are booming: with a few clicks, text messages will contact friends or social media, employ GPS to pinpoint a location and automatically connect to 911. Many will connect to campus security offices and national emergency hotlines. Others use countdown timers that will automatically send messages and GPS information if a user is past due at a destination. Some apps use a Bluetooth connection to pair with a panic button that can be carried on a keychain to send a quick alert without the need to fish out a phone from a purse or bag.