How Do Free Apps Make Money
How Much Does it Cost to Maintain an App
App maintenance is an ongoing investment to ensure your app continues to meet user expectations, stays competitive in the market, and remains secure and functional.
Ideally, a basic App Maintenance Cost Plan of 160 hours per month will do a fair job to manage and upkeep a commercial version of your App and this would cost you less than $ 3000/ Month. Now depending upon the needs, number of App users, number of requests/ issues reported etc.
Source: https://www.agicent.com/blog/h....ow-much-does-it-cost