Flutter Cross-Platform App Development
Production Flutter engineering for Android, iOS and web from one codebase — built by a security company, so authentication, secure storage, API hardening and release integrity are part of the architecture rather than a later remediation cycle.
Verified Solvex Specialist
Verified by SolvexDirect specialist contact for Solvex engagements
What this means. An authorized Solvex administrator registered and approved this exact public identity. What it does not. Solvex has not inspected the account on the platform, and this is not the platform's own verification.
Solvex specialists never ask for your passwords, recovery phrases, one-time codes, or payments to a personal account. Work, scope and invoices are agreed in writing through the official channels on this site.
What's covered
- Product and technical architecture, state management and module boundaries
- Flutter/Dart engineering with responsive layouts across phone, tablet and web
- Authentication, session handling and secure local storage (Keychain / Keystore)
- API integration with certificate handling and transport hardening
- Push notifications, payments and analytics integration where required
- Widget, unit and integration test suites, plus CI/CD to store release
- Accessibility, performance profiling and startup-time optimisation
- Play Store and App Store submission support and release checklists
What you receive
- Complete source code with a documented architecture
- Deployment pipeline (CI/CD) configured and running
- Automated test suite and coverage summary
- Mobile security baseline: storage, transport, authentication and release integrity
- Store release checklist and submission support
- Handover documentation and a walkthrough session for your team
Evidence and reporting
How the work is kept honest- Evidence, frozen at issuanceFindings tie to something observed. When the report is issued, the evidence behind it is frozen in the same transaction and cannot be edited afterwards.
- A signed reportAn Ed25519 signature covers both the report content and the delivered file. Alter a byte of either and verification fails.
- Written scope firstAdvisory work runs to a written scope agreed before it starts, so what you receive is what was agreed.
Anyone holding a Solvex report can verify it publicly without seeing its contents.
Our boundaries
What this engagement does not do, stated before it starts.
- Ongoing feature development after handover is a separate engagement
- Backend systems are scoped separately unless included explicitly
- App store approval decisions rest with Apple and Google, not with us
- Third-party SDK behaviour remains the responsibility of its vendor
How this engagement runs
- 01
Intake
Tell us the system, the goal and the constraints. If the work is not a good fit, we say so before anyone is invoiced.
- 02
Scope and authorization
Written scope and signed authorization before anything is touched. Security testing runs only against systems you own or are contractually entitled to have tested.
- 03
Investigation or build
Specialists matched to the work. Findings are proven by hand — scanner output is a lead, never a finding.
- 04
Evidence
Every finding ties to something observed. When a report is issued, its evidence is frozen in the same transaction, so what backed the report cannot change afterwards.
- 05
Delivery
A signed report: an Ed25519 signature over both the content and the file, with a short verification reference you can read down a phone.
- 06
Verification and retest
Anyone holding the report can verify it publicly without seeing its contents. Fixes are retested as part of the engagement — “fixed” means we confirmed it.
Questions we are asked
- Why hire a security company to build the app rather than a normal agency?
- Because the expensive defects are architectural. Where credentials live, how sessions expire, what the app trusts from the server, what ends up in logs and backups — those decisions are cheap at design time and costly to unpick once the app has shipped and has users. We make them deliberately, and document why.
- One Flutter codebase for both platforms — what is the catch?
- Flutter shares your UI and business logic, but platform integrations (biometrics, secure storage, push, deep links, payments) still need per-platform work and per-platform testing. We scope that explicitly rather than pretending it disappears.
- Do we own the code?
- Yes. You own the source, the pipeline and the documentation outright at handover. There is no runtime licence, no hosted dependency on us, and nothing that requires a retainer to keep working.
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