The PTKD mobile app security guide

    This is the master guide for teams building secure mobile apps from scratch. It walks through the four pillars — threat modelling, the OWASP Mobile Top 10, secure SDLC practices, and incident response — and shows where each linked guide in this cluster fits in.

    If you're new to mobile security, read this hub end-to-end and then drill into the platform-specific clusters for Android or iOS. If you're here because PTKD flagged a finding, skip to the sections matching that finding.

    0 guides in this cluster

    The four pillars of a secure mobile app

    1. Threat modelling.Before code: who attacks your app, why, and what damage looks like. STRIDE applied to mobile gives you six categories — spoofing, tampering, repudiation, information disclosure, denial of service, elevation of privilege.
    2. OWASP Mobile Top 10 coverage.Every shipping app should have a documented stance on each of the ten categories: which ones apply, which controls mitigate, which ones you've accepted.
    3. Secure SDLC.Scanning in CI, threat-model updates per feature, security review for manifest and entitlement changes, dependency scanning, signed builds from short-lived credentials.
    4. Incident response.When a vulnerability is reported — by a researcher, PTKD's scan of a competitor's app, or a real exploit — you need a documented disclosure path, expedited-review playbook, and customer communications template.

    If you're starting from zero

    Three months is a reasonable budget for a small team to get from "no security work" to a defensible shipping posture. The sequence:

    • Week 1–2: Run PTKD against your current build. Triage findings by severity. Document what's in scope vs accepted risk.
    • Week 3–4: Fix the M1/M5/M9 findings (credential storage, network security, data storage) — these are the biggest wins per hour.
    • Month 2: Wire PTKD into CI/CD; fail PRs on high-severity findings. Add Play Integrity / DeviceCheck attestation.
    • Month 3: Threat-model your top five user flows; document accepted risks; write incident response playbook. Annual review cadence locked in.

    Where each PTKD cluster fits

    All guides in this cluster

      Frequently asked questions

      Do I need a security expert on staff to ship a secure app?
      Not for the first year. Automated scanning (PTKD or equivalent), a documented threat model, and incident response playbook get a small team most of the way. Bring in expert help for compliance audits (HIPAA, PCI, SOC 2), threat-modelling complex multi-tenant flows, and penetration testing once a year.
      What's the minimum security review cadence?
      Per-commit automated scanning catches regressions. Quarterly threat-model review catches drift. Annual external penetration test catches what automated tools miss. If you can only do one, choose per-commit scanning — it has the highest catch rate per dollar.
      How much should mobile security cost as a percentage of engineering?
      About 5–10% of engineering time on average. Higher early (10–15% in the first three months) as you fix the existing debt, then steady state at 5% once you have CI/CD scanning and a security backlog. Specialist firms charge 0.5–2% of revenue for ongoing security partnership.