Seems like the author hasn't played through the game yet. Heartopia does have stamina, which can easily be regenerated by eating foods you cook or buy or pick/harvest. Cooking doesn't take long so it's pretty easy to have something to refill stamina. You can actually build with friends in the game. Aside from the mentioned "hobbies" (cooking, gardening, etc.), there are tons of other things to enjoy in the game. I, for one, love buying puzzle pieces and then doing them to display in my home. You can also do painting which can be displayed in your home or even use as a design for your clothes or furniture. There are few daily requests, for me, but there are tons of things to do in the game. I can spend the whole day playing Heartopia, just gathering stuffs & selling so I can make my home bigger & better. I'm waiting for the official release because I loved playing the beta & final tests! IAP also ain't that pricey so kudos to the developers for not being too greedy! 💕
