Google play store is the market of android apps and games. It comes with all android smartphone inbuilt. Just need to register with gmail account to access the store. All type off apps you will get here, not only apps there is lots of games for playing. Maximum apps and games are free to download no need to pay anything for apps. All apps and games are virus free on google play store, so it is not harmfull for your android device. I always use google play store to download apps and games.