Launch Ready cyber security Checklist for mobile app: Ready for paid acquisition in marketplace products?.

Launch Ready cyber security Checklist for mobile app: Ready for paid acquisition in marketplace products?

"Ready" for a mobile marketplace app is not "the app opens and users can tap around". For paid acquisition, ready means a stranger can install, sign up, browse, buy or list, and complete the core action without exposing customer data, breaking auth, or creating support debt the same day you start spending on ads.

For this product type, I would define ready as: zero exposed secrets, no critical auth bypasses, production DNS and SSL working on every domain and subdomain, email authentication passing, uptime monitoring active, and the app stable enough that a spike from paid traffic does not trigger downtime or account abuse. If any of those are missing, you are not launch ready. You are buying traffic into risk.

For marketplace products specifically, the bar is higher because you usually have two-sided trust problems: buyers need safe checkout and sellers need protected accounts. A weak setup here does not just hurt conversion. It creates fraud, spam signups, chargebacks, fake listings, support load, and app store review delays.

If I were auditing this before paid acquisition, I would ask one question first: "Can we safely spend money to send 1,000 new users here tomorrow?" If the answer is anything other than yes with evidence, it needs a hardening sprint.

Quick Scorecard

| Check | Pass criteria | Why it matters | What breaks if it fails | |---|---|---|---| | DNS and domain setup | Primary domain resolves correctly; redirects are consistent; no mixed content | Users and ad clicks must land on the right place | Broken landing pages, SEO loss, ad waste | | SSL everywhere | Valid TLS on all domains and subdomains; no certificate errors | Protects sessions and trust | Browser warnings, blocked logins | | Cloudflare in front | WAF/CDN enabled; DDoS protection active; caching configured | Absorbs spikes from paid traffic | Outages during campaigns | | Secrets handling | Zero secrets in repo or client bundle; env vars only in secure runtime | Prevents account takeover and data leaks | Exposed API keys, fraud, breach | | Auth hardening | No auth bypasses; rate limits on login/reset/signup; MFA for admin | Stops abuse at the highest-risk entry points | Fake accounts, takeover attempts | | Email authentication | SPF, DKIM, DMARC all passing for transactional mail | Login emails and receipts actually deliver | Password reset failure, phishing risk | | Production deployment | Correct build promoted to prod with rollback path | Reduces release mistakes under pressure | Bad release takes down acquisition funnel | | Monitoring and alerting | Uptime checks + error alerts + log visibility active | Detects failures before ad spend burns | Silent downtime, delayed incident response | | API performance | p95 API latency under 500 ms for core flows | Paid traffic exposes slow backends fast | Drop-off during signup/checkout | | Mobile release safety | App store metadata correct; crash-free sessions high; privacy disclosures aligned | Avoids review delays and trust issues | Rejection, poor reviews, install drop |

The Checks I Would Run First

1. Domain and redirect chain

• Signal: The app website resolves cleanly from the ad landing URL to the final canonical domain in one hop or less.
• Tool or method: `curl -I`, browser devtools network tab, Cloudflare dashboard.
• Fix path: Set one canonical domain, force HTTPS, remove redirect loops, align subdomains like `api.`, `app.`, `www.`.

2. SSL certificate coverage

• Signal: Every public endpoint shows a valid certificate with no browser warnings.
• Tool or method: SSL Labs test plus manual check on iOS and Android devices.
• Fix path: Issue certificates for root domain and required subdomains through Cloudflare or your host. Renew automatically and remove any hardcoded HTTP links.

3. Secret exposure audit

• Signal: No API keys, service tokens, private URLs with credentials, or Firebase/Supabase admin keys in GitHub history or frontend bundles.
• Tool or method: Secret scanning in GitHub plus grep across repo builds.
• Fix path: Rotate exposed secrets immediately. Move sensitive values to server-side env vars only. Rebuild client bundles after cleanup.

4. Auth abuse controls

• Signal: Signup, login, password reset, invite flows have rate limits and do not reveal whether an email exists.
• Tool or method: Manual abuse testing plus API request replay with Postman or Burp.
• Fix path: Add throttling per IP and per account identifier. Return generic messages. Lock down admin routes with stronger auth.

5. Email deliverability

• Signal: SPF passes alignment checks; DKIM signs outbound mail; DMARC policy is at least quarantine once verified.
• Tool or method: MXToolbox or Google Postmaster Tools plus test sends to Gmail/Outlook.
• Fix path: Update DNS records through your email provider. Separate transactional email from marketing email if needed.

6. Monitoring and rollback readiness

• Signal: You know within 5 minutes if the site is down or error rates spike above baseline.
• Tool or method: UptimeRobot/Better Stack/Datadog plus a rollback checklist.
• Fix path: Add uptime checks for homepage/API/login paths. Set alerts for 5xx errors. Keep last known good deploy tagged.

Red Flags That Need a Senior Engineer

1. Secrets have already leaked If an admin key was pushed to GitHub or pasted into a client bundle once already, I would not treat that as a small cleanup. Rotation has to be immediate because attackers scan public repos fast.

2. Auth is handled by custom code without tests Custom login logic often looks fine until someone finds account enumeration or bypasses password reset rules. That becomes expensive once paid traffic starts creating thousands of new accounts.

3. The app uses multiple domains without clear ownership Marketplace stacks often spread across marketing site, app shell, API host, email provider links, and payment pages. If DNS is messy now, you will get broken redirects and lost attribution later.

4. You cannot explain where logs live If no one can answer where errors are logged or who gets alerted at 2 a.m., then incidents will be discovered by users first. That means refund requests before fixes.

5. The current setup has already caused support pain If you have seen "reset link expired", "email never arrived", "my account was locked", or "I got logged out after signup", paid acquisition will magnify those failures immediately.

DIY Fixes You Can Do Today

1. Check every public URL manually Open your main domain on desktop and mobile. Verify HTTPS loads cleanly and that `www`, non-`www`, `app`, and `api` behave as intended.

2. Search your repo for secrets Look for `.env` files committed by mistake, hardcoded keys in frontend code, webhook secrets in logs, and service credentials in README files.

3. Test your password reset flow Send reset emails to Gmail and Outlook accounts you control. Confirm delivery time stays under 2 minutes and links open correctly on mobile.

4. Turn on basic monitoring now Add uptime checks for homepage and login endpoints today. Even free monitoring is better than waiting until ad spend starts disappearing into downtime.

5. Review app store privacy details Make sure your privacy policy matches what the app actually collects. Mismatches here can slow review or create trust issues after install.

Where Cyprian Takes Over

Here is how I map common failures to the Launch Ready service:

| Failure found in audit | What I do in Launch Ready | Timeline impact | |---|---|---| | Broken DNS or redirect chain | Fix DNS records, redirects, canonical domains, subdomains | Same day inside 48 hours | | Missing SSL or mixed content | Install/repair SSL coverage across all public endpoints | Same day inside 48 hours | | Exposed secrets / unsafe env handling | Rotate secrets; move config to secure environment variables; verify build output contains nothing sensitive | Same day inside 48 hours | | Weak Cloudflare setup / no DDoS protection | Put Cloudflare in front with caching rules and protection settings tuned for launch traffic | Same day inside 48 hours | | Email delivery failures | Configure SPF/DKIM/DMARC correctly for transactional mail domains | Same day inside 48 hours | | No production deployment discipline | Deploy production build safely with rollback notes and handover checklist | Within 48 hours | | No monitoring / no visibility | Set uptime monitoring on critical paths plus alerting handover so failures are caught early | Within 48 hours |

My recommendation is simple: if you are planning paid acquisition in a marketplace product category while any of the above items are unresolved, do not buy more traffic yet.

Launch Ready is built for this exact gap:

• Domain
• Email
• Cloudflare
• SSL
• Deployment
• Secrets
• Monitoring

That includes DNS cleanup, redirects, subdomains, Cloudflare, SSL, caching, DDoS protection, SPF/DKIM/DMARC, production deployment, environment variables, secrets handling, uptime monitoring, and a handover checklist so you know what is live before you scale ads.

If your mobile app needs to survive marketplace traffic without leaking data or collapsing under load, this is the right first move. It is cheaper than one week of wasted ad spend plus support cleanup after launch failure.

References

• roadmap.sh cyber security best practices: https://roadmap.sh/cyber-security
• roadmap.sh api security best practices: https://roadmap.sh/api-security-best-practices
• roadmap.sh code review best practices: https://roadmap.sh/code-review-best-practices
• OWASP Mobile Top 10: https://owasp.org/www-project-mobile-top-10/
• Cloudflare security docs: https://developers.cloudflare.com/security/

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Take the next step

If this is a problem in your product right now, here is what to do next:

• [Use the free Cyprian tools](/tools) - estimate cost, score app risk, check launch readiness, or pick the right service sprint.

• [Book a discovery call](/contact) - I will tell you honestly whether you need a sprint or if you can DIY the next step.

*Written by Cyprian Tinashe Aarons - senior full-stack and AI engineer helping founders rescue, launch, automate, and scale AI-built products.*