This App Lets You Say 'Yo' to Your Contacts. That's It. (Wait, Is It?) Moshe Hogeg had a problem: He was tired of sending countless text messages to his assistant, asking her to come into the room. So Hogeg, CEO of the photo and video sharing service Mobli, asked Or Arbel, a former iOS designer at the company, to create a solution. What Hogeg wanted, as Arbel recalls, was an app that had "one big