If apple slices are a preferred snack for you and/or your kid but you get sick of cutting those slices individually all the time, you should get the OXO Good Grips Apple Slicer. Just press the sharp stainless steel blades downward and boom, you've got a perfectly sliced and cored apple, every time. It only takes a few seconds.

The oversized raised rubber handles make the slicer comfortable to use, and when you're done, the whole thing can be easily rinsed off or put in the dishwasher if you like. Also works well for slicing pears.

This is one of the few single-purpose kitchen tools worth keeping around. Get it for $10 on Amazon.