I don't think this will work. There are plenty of free tool apps already established. You'd need to find a unique one and heavily market it. Even that has a low

I don't think this will work. There are plenty of free tool apps already established. You'd need to find a unique one and heavily market it. Even that has a low chance of success. The most money I made on apps was the $250 settlement money Google paid as part of that class action.