Is there an Inflate/Deflate Mesh option in Blender? I want to know if there is a tool that I can use to inflate a mesh like a balloon or a cube or anything else. And the same question, just for deflate, so a cube goes in on itself (collapses).
CharlesL's answer is the closest thing to what you ask but adding this as it can produce some interesting results. You could experiment with the Simple Deform modifier set to Stretch and adjust the factor.