Well, you can make money online with Android-powered smartphones (iOS too, just I'm more focused on Android). With the right apps installed on your Android phone, you can earn extra income or even turn your device into a source of passive revenue. There are Android apps that reward you for doing some actions (i.e. filling out surveys), or others that simply pay you a referral fee for sending in new users. Below are some of the highest-paying apps for Android that I've also tested and can be extra income sources (this list is being continuously updated):