People who like mobile apps and mobile technology.
Having knowledge of Android or iOS coding will give you an advantage but it's not necessary. Nowadays there are many online app maker tools available online using which you can create professional level apps without coding.
Here's the list of few popular app maker tools:
Depends on the expertise of the app developer and scope of the app.
1. Upload a free app on Android’s Play store and Apple’s App Store. Monetize it with AdMob, Google’s mobile advertising network.
2. Upload a paid app, set some initial price for downloading the app.
3. More people will download your app more money you will make.
4. You can also promote affiliate products through your app and earn extra commissions.