Creating an animation can be time consuming, however I feel that photoshop has made it easier in a sense that you use layers most of the time. For instance, when using other types of programs for 2D animation it seems to be more complicated. Where as, with Photoshop I followed a few simple methods, additionally it was a bit easier to use this feature having worked with photoshop for a long while. The animation of (dolphins) can be seen in the uploaded GIF file.
Working with animation in Adobe Photoshop