App-Entwicklung: React Native Modernisation

React NativeModernisation

An older React Native app battling outdated dependencies, accumulated architecture, and technical debt costs your team energy every day. We analyse the current state, prioritise the highest-impact measures, and modernise incrementally – without jeopardising live operations and without rewriting everything at once.

Challenges you'll recognise

  • Your React Native app is on an outdated version and you are afraid to update major dependencies.
  • Every new feature takes disproportionately long because no one fully understands the existing codebase anymore.
  • The app becomes unstable on newer iOS or Android versions – but the state of the code makes targeted fixes risky.

Dependency Audit

Outdated packages, deprecated APIs, and incompatible libraries are the most common causes of instability in older React Native apps. We systematically analyse all dependencies, identify security vulnerabilities, and create a prioritised update plan with clear test strategies for each update.

Architecture Refactoring

Grown codebases often lack clear separation of concerns, have components that are too large, and contain implicit dependencies. We refactor incrementally: starting with the most critical, highest-risk areas – always with tests as a safety net and without changing features simultaneously.

React Native Upgrade

React Native major upgrades are often more effort than expected – especially when native modules are involved. We guide upgrades with a structured process: Upgrade Helper, isolated native changes, and cross-device testing ensure the upgrade lands stably.

Performance Analysis

Slowness in older apps usually has clear causes: unnecessary re-renders, unoptimised lists, too many bridge calls, or missing memoisation. We measure first – with profiling on real devices – and then optimise the spots with the greatest impact.

Good to know

  • Analyse Before Acting

    We begin every modernisation with a structured inventory of the current state. Without understanding the as-is situation, any change risks unexpected side effects.

  • Tests as Safety Net

    Tests come before refactoring. Characterisation tests that document the current behaviour make modernisation safe – even without complete test coverage in the existing codebase.

  • Incremental, Not Big Bang

    Modernisation happens incrementally with continuous deployments. The app remains releasable at all times and the risk of a large migration project is spread out.

Frequently asked questions

Do we need to rewrite everything or can we modernise incrementally?
In most cases incremental modernisation is the right approach. Complete rewrites carry a high risk of losing features or introducing regressions. We analyse what delivers the highest impact with the least risk.
How is it ensured that modernisation does not introduce new bugs?
Through tests as a safety net before every change. For areas without tests, we write characterisation tests that capture the current behaviour first – then we refactor.
How do you prioritise which debt to pay down first?
By risk and impact: security vulnerabilities and unstable areas first, then the parts that are changed most frequently and therefore cost the most development time. Purely aesthetic improvements come last.

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Why nextlevels

Success you can measure

With us you're always one step ahead technologically and tap directly into our extensive app development expertise. We take a close look at your app idea, identify key success factors and create tailor-made applications. Your visions and goals are at the heart of our joint project work.

  1. Expert knowledge in app technologies

    React Native, Flutter, native iOS and Android — we pick the stack to fit your project, not our preference.

  2. Comprehensive user experience know-how

    Intuitive operation and seamless interactions decide ratings and how long users stay in the app.

  3. Proven track record

    Published apps in the App Store and Play Store — from MVP to mature platform.

  4. Versatile team

    Concept, design, development and backend from one hand — no friction at the interfaces.

  5. Long-term partnerships

    We stay after launch and keep evolving your app with maintenance and updates.

READY FOR YOUR APP THAT SETS NEW STANDARDS?

Whether you want to optimize an existing app or bring a new vision to life – we'd love to meet you. A no-obligation conversation is always a great start.

Profile picture of Paul Kalisch, Executive Partner
Paul Kalisch
Executive Partner

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