This app has lots of simple games for learning numbers. My daughters interest wasnt grabbed, so they arent great games, but they are okay.
The interface did have a lot of frustrating things. For example - in 1 game you feed a hippo some food. If you touch an apple, it moves to the hippo. The hippo only accepts the food (e.g. counts it) if its mouth is open when the food arrives, as opposed to when it is touched. But, there is about a 1 second delay from when you touch the food to when it arrives. Its a subtle game mechanic that is frustrating (and not easily understandable) by the age grip that this app is made for. From a 2-3 year olds perspective, they touch an apple (she the hippos mouth is open), but the hippo doesnt eat it. This is too confusing.
Also - the rewards screen where you get to dress up a snail also has a bad interface. You have to swipe at a certain speed to move between different things you can put on the snail, but if you swipe at a slower speed then you pick up the items to drag them to the snail. So, trying to move slowly through the items you can use is very frustrating because you always end up dragging the item rather than moving through them. There is really no point in having the drag a hat (for example) to the snail, since you have no choice in where it ends up. Why not just make it tappable rather than have 2 conflicting drag/swipe based gestures?
gevason about 123 Kids Fun NUMBERS - Top Fun Math Games for Kids, v1.3