Android & Web Phone Scanner

I’m building a service that lets users run deep scans on their Android phones from either an Android app or a responsive website, then subscribe on a monthly or yearly plan for ongoing protection.

Core scope
• Android app – the main interface for running device scans, viewing results, and managing the subscription.
• Website – mirrors the scanning dashboard so users can trigger a scan, review reports, and purchase or upgrade a plan directly in the browser.
• Unified backend – handles the actual scan logic, report storage, in-app purchases, Stripe/PayPal recurring billing, and future expansion to link and installed-app scanning.

Key functions I need implemented
1. Device scan engine that checks the phone for malware, risky permissions, outdated OS versions, and other common threats.
2. Secure user accounts with email, Google, or Facebook sign-in.
3. Subscription flow: free trial, monthly plan, annual plan, automatic renewal, and graceful downgrade on payment failure.
4. Admin portal where I can push definition updates, see active users, and trigger announcements.
5. Clean, modern UI that carries the same look across web and Android (Material-style is fine).

Tech preferences
– Kotlin or Flutter for the Android build.
– React, Vue, or similar for the web frontend.
– Node.js, Django, or Laravel for the backend; I’m open as long as it’s secure and well-documented.
– Stripe is my first choice for billing integration, though I’ll consider alternatives you recommend.

Acceptance criteria
• Full source code in Git with clear README for local setup.
• Successful scan on at least two Android test devices.
• Subscriptions charge correctly in sandbox mode and switch to live with one config change.
• Deployed to my Play Console and production server (AWS or DigitalOcean, whichever you prefer) with HTTPS.

If you’ve built security or subscription-based apps before, share a brief example. I’m ready to start as soon as we agree on milestones and timeline.