You're doing the right thing in calling people first before diving into code, but I suggest you do so as part of a process - see Steve Blank's Customer Developm

You're doing the right thing in calling people first before diving into code, but I suggest you do so as part of a process - see Steve Blank's Customer Development methodology: http://www.startuplessonslearned.com/2008/11/what-is-customer-development.html http://www.startuplessonslearned.com/2008/11/what-is-custome... http://www.slideshare.net/venturehacks/customer-development-methodology-presentation http://www.slideshare.net/venturehacks/customer-development-... Also, what kind of products are you building? Developer tools? B2C? B2B? Ideally you should build something at least tangentially related to your domain expertise or tools expertise.