Highly addictive but fun! UPDATE: It was fun until it started crashing all the time. Ads have to be watched multiple times now to get a perk and they're the same stupid ads for games I have no interest in. Spent a little money on the game because I do believe in supporting good work but the crashing is getting ridiculous. I thought I had paid to remove the ads but apparently not. Putting up with all the ads really takes away from the fun. Wish there was more information about boosters.