I've covered my development costs, and I am breaking even after just 40 days of accepting customers, but the growth is tiny and a very small piece of what it could be. With that being said, going after the market at large requires at least a couple more employees, and some PR/marketing, that I can't afford from my current revenue/pocket.
Congrats on finding a quick win. The decision to seek investment really depends on your performance to this point, scalability, market potential and what you expect to give up in terms of equity. If you can grow without outside investment, I'd recommend it. Think about cheap sources of labor - we use interns for dev work depending on their experience level and skills. PR/marketing can be done in other ways besides the cookie cutter corporate campaigns. Look to debt or other sources of financing before making a decision to give up equity.
I'd be happy to talk about your platform and possible options. Send me a message if you'd like to find a time to meet.