Check out the StartUpsForTheRestOfUs.com podcasts . . . there are a few episodes on shipping with an initial feature set to start getting feedback from paying c

Check out the StartUpsForTheRestOfUs.com podcasts . . . there are a few episodes on shipping with an initial feature set to start getting feedback from paying customers . . so you can see what real customers want/are using before you spend time on features/additions that might not even be useful to paying customers. There are also some episodes on marketing, SEO and building an email list . . . I would recommend getting started right away on a website/landing page and building an email list. If the feature he wants is a 1 or 2 week thing maybe you can start ramping up marketing while the feature is being completed. Check out articles/podcasts with patio11 and amy hoy as well . . . they are all fans of launching early to validate your idea, get feedback from paying customers and start generating revenue. Good luck with the launch.