If you are using Android Phone & live in US, And want to kill some time answering really short surveys for Free Google Play credit.
Go Ahead and Download this app from the play store. Google Opinion Rewards
Answer quick surveys and earn Google Play credits with Google Opinion Rewards, an app created by Google Consumer Surveys.
Getting started is easy. Download the app and answer basic questions about yourself. We’ll then send you surveys around once a week, although it may be more or less frequent. You’ll get a notification on your phone when a short and relevant survey is ready for you, and can receive up to $1.00 (USD) in Play credits for completing it. Questions can range from, “Which logo is best?” and “Which promotion is most compelling?” to “When do you plan on traveling next?”
This is currently only available to users located in the US.