The good is it’s quick and intuitive to toy around with. The bad is, it’s not a serious app.
I’m on an iPad 4. The sliders to adjust size are operating crudely, and there is no option to type it in manually. It’s constantly off by a few mill. This is annoying when you place two similar objects (windows) adjacent to each other
Even when the size is exactly the same there are visual anomalies in 3D view. Let alone when they differ.
Several objects don’t show up. Overlapping two patterns confuses the app(See the official demo 1)
Very limited amount of objects and most annoyingly the scale is all over the place. Hilarity ensues but really it is just amateurish.
No terrain option. You can make a room and “remove” the walls by making holes, but they don’t extend beyond the corners. So in 3D view you’re left with a weird flag pole. Of course no 2nd floor, roof, lamps.
Fix all that, and consider making a copy or repeat option(stairs, windows), and a lock or group function to keep separate objects at their correct relative distance.
...And maybe you could start charging money for it.