Honestly you could go for an optional subscription of some sort and make it dirt cheap like $3/month. I know many people (like myself) want to support this but would rather do it monthly, and if you offer it in the app non-intrusively with just a single reminder then you'd probably get the exposure to make those $3/month subscriptions add up. Maybe add a couple perks that wouldn't seem unfair like dark mode or priority when submitting articles or something. Giving attribution to who submitted the article would probably also boost submissions if you go that route.

Also I'm a software developer and would love to volunteer my free time to bring it to Android or implement features if you need more assistance. It's a great idea that I can get behind. Just give me a DM if you're interested