Answer a question, pay for that in-app purchase in Candy Crush
The Google Opinion Rewards app has just launched in the Play Store, and it may be a good way to build up your Play Store credit balance. The idea isn't new — after you download the app, you'll occasionally be asked to answer a handful of questions, and you'll be rewarded with money to spend on apps, movies, books and music in the Play Store.
Google says the surveys will show up about once a week, and you'll be notified on your phone when a survey is ready to be answered. The questions will be simple and range from things like "Which logo is best?" to "When do you plan on traveling next?" The app is currently U.S.-only, and it isn't clear how much Play Store credit you'll get for answering each survey.
You can download the app (from the Play Store link above) right now and answer a few questions about yourself, and then wait for the first real surveys to come in.
Source: +Google Consumer Surveys