4 stars: It is a really amazing game. this is quite a game i like to play on daily basis. The UI is good, the game has good features. Except for the cost of the coins, they are pretty expensive. I am not someone who like to pay to win. Collecting coins for upgrade is very difficult for new players and need optimization in my opinion.
3 stars: it's a pretty cool and unique game, however the game is very pay to win oriented in my opinion (if you have the premium currency gold, you can essentially do anything). Additionally there aren't really tutorials for certain things such as auctions and etc in game. Lastly it doss take quite a while to wait for your upgrades/purchases unless you have gold to skip timers.
3 stars: The game is good, not one that you can play for hours at a time but it's one where you can check in ever so often, the adds are entirely optional and you get rewards for watching them which is good, I do wish there was more of a tutorial cos it took me a while to get into and I am still unsure on some aspects of the game. I there is FAQ's but there not that helpful. If there was a tutorial it would be a solid 4 stars.
2 stars: I have mixed feelings on the latest release in July. It added some cool rewards, but ultimately I think it's harder to get coins for free. At least harder to get coins for free without watching ads. Now it seems like the only way to get coins is by watching a series of videos. The prior reward system would periodically give coins...