GetXAPI is the cheapest Twitter API and X API. $0.001 per call returns ~20 tweets ($0.05 per 1,000). Fetch tweets, profiles, followers. No dev account.

Full stack engineer

HeyNews reads a newsletter's back catalog, learns how its writer actually sounds, and drafts new issues in that voice. It monitors sources across RSS feeds, blogs, Reddit, and social media, scores relevance, and returns a publish-ready draft. The creator reviews and sends every issue; nothing auto-publishes. Native beehiiv API and Kit OAuth integrations, plus archive import from any other platform such as Substack and Ghost. Sold as self-serve plans and as done-for-you newsletters for companies.

Web-based AI image editing tool for creators and small businesses. Users upload an image and get a polished, AI-edited result in under a minute - no design skills needed. Monetized through Stripe with pay-as-you-go credit packs plus monthly and annual subscriptions. Fully automated, solo-operated, ~90% margin. Traffic is organic (search + social), no paid ads.

It's AI service for photo colorization and restoration

coldcaller.pro is a French B2B prospecting SaaS selling qualified cold-calling leads to solopreneurs and agencies. Leads come enriched with the owner's direct mobile + email. Subscriptions €19–99/mo, no free trial, ~9% visitor-to-paid conversion, €2.4k MRR with minimal fixed costs (93% margin). 100% community driven acquisition (word of mouth). Runs solo — big upside with paid ads or a sales team.