Excerpt from this article:
It seems like every new app you download these days practically begs you to turn on notifications, or the ability to send you alerts when the app isn’t running. Sometimes these alerts are useful, as in the case of apps that tell you when a taxi has arrived or a message has been received. But there are many more apps—music, travel, games—that simply want your attention for their own benefit. A new report from Localytics, an analytics firm, explains why.