The idea of abandoning the 9 to 5 job to strike out on your own can be strong. There are many stories where a solo entrepreneur or small startup team did just that, and are now well off, if not insanely rich.
But the other 90% you never hear about. They work hard to try and get their idea to market, but it never pans out. A myriad of reasons can cause a project to fail, long before it replaces your salary today.
Your personal circumstances along with talent and drive, should play a pivotal role in deciding to make the jump. Unless you have a comfortable amount to savings, I would recommend keeping your day job and working on the side project in your spare time. Don't quit your W2 until you get some real traction on it.