Most great ideas come from something that already exists, and we tweak and refine it to make something better. Instead of worrying about the potential copycats, focus on the new product and how you can get out to market with a very friendly e-commerce site so people can purchase it quickly.

This reminds me of when Steve Jobs named his computer Apple Lisa - http://en.wikipedia.org/wiki/Apple_Lisa

If the domain represents the product, it needs to be marketed so that everyone knows what Melissa is (http://meetmelissa.com/ ) which is available.

This way you can educate and provide an introduction of your product. Again you would really need to market that brand persona so there is no confusion that "meeting" Melissa is your home automation system.

Hi,

Get involved with your audience. If it is an app about the restaurant business, start talking to local dining establishments and see how you can work together to promote.
Another great tool (depending on where you are located) is using meetup.com to meet with like minded individuals to network on topics of discussion.
Wherever your mobile app is supposed to live (in the hands of smart phone users), go there and engage with those potential users. They will probably be excited to share with you their thoughts on the App.