I'm a sophomore in college who has a small non-startup product business that's started taking off. I develop Mac software. It's been paying off well for the small amount of time I've been able to sink into it, and there's a lot I could do to serve my customers better and attract more business. Kind of exciting.
But I'm also interning at a company. I've interned at a few before. Since I've just had the first month where I made more off my own business than wages from the internship, it's made me re-evaluate a lot of things. It feels really weird.
While I could quit the internship and lose credit for it, and funnel all my energy (instead of a couple hours a day) into improving my own business...something in that doesn't appeal to me.
In a way, I kind of want to be a corporate slave for a few years. I'm learning a little about business and working with other people. I really need to have some daily interaction with other human beings to stay sane. I also recognize a lot of gaps in my non-technical skills that I'm going to need experience to fill.
But on the other hand, it's also extremely frustrating and demotivating at times. Everything happens really slowly with a lot of BS in the way. And, even though I've taken some initiative in the company and contributed to a lot of projects...you can't entrust any kind of responsibility to an intern, and you definitely can't promote one. Unlike when I'm working for myself, there's no advantage to figuring out more efficient ways of doing things or pressing myself to work harder.
So I find myself being less effective than I would otherwise be just because of the environment. Most of the interesting, technically-challenging work is given to other people, and, if not, attributed to other people upon completion.
And, because of my own business competing for my time, often the slightest little indignity will make me think about quitting and be really grumpy for a couple days.
So what would you do? I don't want to burn any bridges, but I want to be happy.
If best comes to best and your software takes off even more, create a particular limit to decide when you will drop the internship and focus 100% on the software. When you're making 5x from the software as your internship; when you are working 2x as much; etc. It's up to your needs and desires.
The bottom line: Internships are meant to either teach you the ropes or to open doors. If you feel yours isn't doing either, then ditch it; you're not getting your effort's worth out of it. If it's at a huge company like mine was (NASA), then it's a sticky situation and you might want to stay the course just for the sake of resume-building.