This one here was made with Desktop Paints Animation Maker. It uses warping to move images around in a single layer. It's good for working quickly, and as long as nothing is overlapping it does a pretty good job. It is inexpensive and also has a free trial, so definitely check it out!Nowadays, I"m mostly using Adobe After Effects for my animations. It's way more expensive and complicated, but lets you do a lot more complicated effects and layers. If you are just starting out, definitely go for DP Animation Maker first