Nerval's Lobster writes: New data from research firm Nielsen shows that — surprise, surprise — Facebook, Google, and Apple dominated the list of most-used mobile apps. Facebook's core app took the top spot on Nielsen's list with 126 million unique users per month, followed by YouTube with 97 million, Facebook Messenger with 96 million, and Google Search with 95 million. This is partially a consequence of the mobile world essentially becoming a duopoly between Google Android and Apple's iOS, meaning that the core apps produced by those companies are always front-and-center (and thus always in use) for the majority of mobile users. But not every app launched by these companies succeeds: While Facebook dominates, for example, the company is notable for some app misfires, including Paper and Facebook Home. That might be cold consolation to indie app developers trying to build up a significant audience.