Unless there's a big difference in using a web vs mobile app (for either listeners or authors), I would suggest starting with a mobile responsive web app. Getting potential users to click on a link to try a product should be easier than getting them to install it to try. It's also much less work: one codebase in tech you already know. If you really want a mobile app, you can use a webview to customize the site further for Android/iOS.

There's also an in-between possibility, if you want authors to have the best UX and they're already motivated to install, make a mobile authors app and web/webview-mobile for listeners.

If all goes well, you may want to reconsider if there is/will be a need to port to more interactive mobile platform. By that time, the hurdle of motivating users to install an app should already have been passed.

Work for a company that is doing this. There are so many intricacies and security points, it really takes years to get good at this.

Are you also new to backend development, database schema design, and devops?

You might look at something like Prisma or Hasura than helps you build a lot of this out.

If you make it this far, you realize tech is not the real problem. Is actually business, sales, and generally understanding problems and communicating solutions so you are building something people actually want.

Hence sibling comment to get a minimal thing out to validate your market hypothesis. Have you dug into startup literature?