PBS Kids has some really great apps and shows! You can trust and know that if PBS Kids has made an app the chances are it’s a pretty good one.
Their app Plum’s Creaturizer is an app that lets you create an animal or creature. Once your creature is created, you take the device out in nature and snap some pics of it in its natural habitat, explaining different aspects of its survival. This app really allows children to synthesize and demonstrate their learning!