It is very difficult to get funding for an app that has not launched yet (there are some exception of course). Your potential investor does not know whether the app has a market or not. Besides most savvy investors are not looking for a product, they are looking for a business to invest in. You have to remember that a single app does not make a company. So, it is better to think in terms of how the company will established and grow its market share. It is better to confirm a product-market fit and gain traction within your target market before asking for funding. This has two advantages: Investor has confidence that app will do well in the marketplace and the company has a future, also you as an entrepreneur you can retain more equity in your app/company.