1. Phonesize.com is an excellent online tool that lets you see the actual size of a phone on your computer screen. An interesting part is that you can compare any phone and model with others in real time.
The service has a large database of most popular smart phones. Just enter the site, simply select phone model from the selection box. To remove one, click the remove button underneath it.
2. Sizeeasy is another excellent service that helps you visualize and compare product size when shopping online.
3. DemoAnywhere is another service that provides virtual handsets, and provides interactive tutorials and demos.
If you considering to buy a new phone online and if size is a matter, I am sure the above three services will certainly help you.