Instant Domain Check (iDomain for short) is an app for quickly searching for .com, .net, and .org domain names & checking for domain availability. It is currently the fastest app that can “reliably” tell you whether a domain name is available or not. Also, iDomain is much faster and easier than loading a domain search website in Safari.

If a domain name is available, you have the ability to register the domain through either GoDaddy.com or NetworkSolutions.com

If the domain name is taken, you have the ability to Backorder it, view name suggestions, do a whois lookup to determine name servers, ownership information, etc, or you can view the website.

The software also features an “Instant” checking feature that can check for domain availability as you type (this works best if you have a fast network connection). You also have the option of using “Standard” mode so that the domain availability is only checked after you click the “Go” button.

http://appshopper.com/utilities/instant-domain-check