I managed to put together a little side project in 3 months and it's sitting at #34 in Trivia in the U.S. app store so I'm a bit chuffed with myself today.
https://itunes.apple.com/us/app/yes-or-no-choice-based-game/...
Yes or No is an app where you can post a question/statement/opinion and people either vote Yes or No. Once you vote you see what percentage of the world agreed with you.
It originally was intended to be simple questions like "Putting the milk in before the cereal - yes or no?" but the best content that was posted are actually unpopular opinions "Americans should have to pass an intelligence test to vote - Yes or No?". The intention is not to offend but simply to be entertained/surprised by the results.
There's other apps like this already but the content is pretty awful and I found their UX to be terrible with some pretty unethical advertisement walls, so I wanted the opportunity to build something better.
In terms of technology I built the app with React Native and the back end is Firebase / Firestore (which I can't recommend enough for bootstrapping).
In terms on monetisation, I have only really stuck in banner ads every 10 posts. It won't make me rich in it's current form but I just want to focus on retention, building an awesome user base and using that for cross-promotion for future apps.