This is a tricky one; you could still market your product without telling the world you're making money.
But what if telling the world you're making money is a great way to market your product?
Even one person knowing about your app (regardless of money) risks someone cloning it, or competition springing up.
If you think you have a chance of staying ahead of the competition (improve UI, improve design, add features, build a community, engage with clients/customers), you should probably shout about your product from the rooftops at every chance you get.
But what if telling the world you're making money is a great way to market your product?
Even one person knowing about your app (regardless of money) risks someone cloning it, or competition springing up.
If you think you have a chance of staying ahead of the competition (improve UI, improve design, add features, build a community, engage with clients/customers), you should probably shout about your product from the rooftops at every chance you get.