this is supported by google and itunes and works very well. It's a very simple way to obtaining free gems. Step 1 : Go to the market place and download the app " app trailers " it has the picture of a FilmReel and is made by AppRedeem Inc. Step 2 : Run the app, and be sure to allow push notifications or your points will not go through. Step 3 : Click the bottom right tab and register your account. Use my referral code "murmasa" this will give both you and I easy extra points. You can do this by going to the video tabs and clicking on " Enter Bonus Code ". Step 4 : Go to the videos tab and watch the 30 second trailers ( I will usually just click watch trailer and do something else ) Step 5 : Be sure to download the app and try it for 2 minutes, App Trailers will notify you when it will count. This gives about 100-200 extra points which is a lot. Step 6 : When you have saved up enough points Itunes users will use points to get an Itunes cards, ( Google Play Card for the Android users ) Step 7 : Use the card to purchase your gems in game Done ! It takes a small amount of work but after all it is free ;]. P.S I would avoid doing the big point offers because most of them will send spam to your phone. The netflix and gamefly ones are legit though.