So how much money can you realistically stand to make from this idea?
To help determine whether an idea is a viable one or not, you should calculate how much money you could potentially make if everyone within your Target Market was to agree to buy your app.
Multiply your Target Market figure by the Product Price for your app, and then cut the total in half to allow for commissions, expenses, etc. This is your Maximum Revenue.
Is this a big enough income to make all your time and effort worth it?
Calculate your Maximum Revenue and ask yourself, is the potential income enough to make this a viable project?