That should be the first thing you do, even as an employee you should know what your competitors are doing.
If no competitors exist in a space, and you're thinking of starting a new company you need to wonder why. There's a good chance there's just not a market for what you want to do. On the other hand, if the markets absolutely saturated with different competitors, what are you doing better than them?
You should know what they are doing and keep an eye on them, but I think it's important to be careful not to copy them and solve problems in your own way.
If no competitors exist in a space, and you're thinking of starting a new company you need to wonder why. There's a good chance there's just not a market for what you want to do. On the other hand, if the markets absolutely saturated with different competitors, what are you doing better than them?