Apptopia is a specialized marketplace created to connect developers with investors interested in getting into mobile.  It's not a service to help developers better market their apps. Instead, it provides an exit strategy. Set to launch later this year, Apptopia aims to give developers an option to make money from the sale of ownership, code, revenues  and more. It will provide end to end service throughout the sales process. Apptopia will interface with Google/Apple on your behalf, as well as provide escrow services and app valuation. The service has been in beta since January 9. "By beta, I mean we have been accepting seller and buyer requests off our site, and I have been running the marketplace completely offline," says founder Jonathan C. Kay. "I quickly realized that if I hustled hard enough, I could absolutely work like an old-school broker and just start putting 2 and 2 together. I wanted to prove out our hypothesis without any doubt, even before we launched our product." Currently, there are over 175 apps available for sale and more than 65 buyers. Two deals have closed, totaling $17,000. Apptopia is set to launch March 1. If you're looking to improve perfomance of your existing apps, Apptopia has a few suggestions.

• Paid apps should be marketed in the Apple App Store
• Free apps work well in the Android Market
• Focus on user experience: Design something worth admiring, especially for iOS devices
• User feedback is important, so don't immediately list version one in a marketplace. Test first
• Involve friends and family in the review process to increase the total number of user reviews
• Measure the effectiveness of your marketing efforts

If you have an app you'd like to sell, now might be a good time to contact Apptopia to see what you can get for your hard work. Good luck!