Backlink Checker is a link monitoring tool that monitors your backlinks & informs you if your backlinks are removed. We charge users in subscription plans or lifetime access to monitor their backlinks.

walldecor.io lets anyone preview wall decor on a photo of their own room before buying. The main hook is the free Wall Art Visualizer: upload a photo, drop in any artwork, and see it framed at its real size on your wall. The paid Lifetime plan ($29) adds wall repainting, wallpaper, and full room makeovers.

ToonThis turns selfies into cartoon, caricature, chibi, crochet-doll and other AI art styles in seconds. Native SwiftUI iOS app, localized in 13 languages. Subscriptions via RevenueCat, 100% organic growth via ASO ($0 ad spend), ~600 new users/month, ~80% margin after AI costs. Lean stack: AIProxy for secure AI calls, no custom backend. Upside: paid UA, Android, more styles. Full handover: source code, App Store transfer, RevenueCat project, docs and 30-day support.