This is a really nice chess app. The challenges are really good and help a lot with mid game/end game patterns. My only disappointment with this app is you have to collect coins to play online, and with any wager you put in you only profit half of your wager. Ex: the lowest level costs 200 coins, both players put that in, and the prize is 300 coins. Same at the highest level, wager 10,000 to win 15,000?! Why is there so much risk when it's just pretend money anyway?