I want to create a custom map (not of any country/state/city) which can be used for navigation. Am looking for any existing tool that can help me do that for both iOS and Android application. The map would not be a earth map but some custom map where I can define the layout and path.
your answer isn't very clear, but do you search for real-life map resources such as openstreetmap provides? They should have an API to integrate in your app.