Hi, 

The leaf curling is most likely due to the heat. Even with consistent watering this can still happen and is quite common. 

The cracking and splitting also looks like a symptom of heat and watering. Also have you fertilized with nitrogen recently? If so that can cause splitting of the fruit. You can try to pick them before they start to ripen on the vine and let them ripen in a sunny window instead to help prevent the splitting. Also if you have a location, maybe try moving them off the brick? It may be keeping them too hot in the black grow bag and the brick patio radiating heat off of the hard surface. You could try to check for watering needs twice a day but the morning would be better if it seems like they are getting too much water. You can refer to our page on common Tomato problems  page but overall we think that it is due to heat and water. 

It may not fully correct this season but maybe a bumper crop later on could be not as cracked especially when the temperatures level out some. 

Emily