Blender is described as 'Free open-source 3D software for modeling, texturing, rigging, animation, rendering, compositing, video editing, and simulation' and is a leading 3D Modeler in the photos & graphics category. There are more than 100 alternatives to Blender for a variety of platforms, including Windows, Mac, Linux, Web-based and iPad apps. The best Blender alternative is Autodesk Maya. It's not free, so if you're looking for a free alternative, you could try Wings 3D or Bforartists. Other great apps like Blender are Autodesk 3ds Max, Cinema 4D, Natron and ZBrush.
Motion is designed primarily for 2D and relatively simple 3D animation, whereas you can model and rig 3D characters in Blender.