Gems are the in App Currency in Clash of Clans you can use to boost buildings and training or buy upgrades without raiding other players. Here are all official and legal working free Gems solutions out there you can use to get coc gems without having to pay with your real money I highly recommend either AppBounty for iOS Clasher and FreeMyApps for Android Clashers. Learn also how you can use USD giftcards in any country of the world.