The "Reward King" app is an Android app that allows users to earn rewards through tasks like solving captchas, spinning wheels, daily check-ins, and referring friends. However, it does not directly provide free Google Play redeem codes. Reviews indicate it is generally considered genuine but with low earning potential, payment delays, and many ads. It is not recommended as a reliable source for free Google Play codes. For actually earning free Google Play credit, Google's official app "Google Opinion Rewards" is a better and safer option. It gives real Google Play credit for answering short surveys. Other trusted reward apps like Swagbucks and PrizeRebel also offer points redeemable for Play Store gift cards, but one should be careful to use reputable services. There are also apps like "FreeGiftZone" and "Freeze Redeem Code" that offer redeem codes or game currency by completing tasks, watching ads, and playing games, which might include some gift card rewards but are third-party and informal methods. In summary, while "Reward King" can let you earn small rewards, it does not give guaranteed free Google Play redeem codes. For genuine Google Play credit, use Google's official Google Opinion Rewards app or trusted rewards platforms.