The iPhone Microscope you see here is just one example of several different versions. I selected this one because it is currently the only one with customer reviews to reference. They all differ in cost range and qualities. Browse through the many different iPhone Microscopes through the following link:
…Browse All iPhone Microscopes here.

As I mentioned, the above iPhone Microscope is just one version. This one has mixed reviews. These iphone microscope adapters will essentially transform your smartphone into a microscope with one simple attachment. This is the Thumbs Up iphone microscope that attaches to the iphone 4. The microscope produces a digital image that you can manually focus on the microscope. This particular microscope magnifies up to x100. Read all product details, reviews, and see more images through the following link:
…More details about this iPhone Microscope here!

Pros: Some good reviews for basic use. A great gadget for some fun and taking some interesting pictures. Many other brands and types to browse through aside from just the one discussed here.

Cons: The reviews are mixed, but a couple people have mentioned that the Thumbs Up iphone microscope has fairly low quality. Read the reviews yourself and judge for yourself.