Viacheslav Kostin
CEO WislaCode Solution
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Mobile App Modernisation
WislaCode offers comprehensive mobile app modernisation services to transform ageing applications into high‑performing, scalable, and secure solutions. Our approach keeps your app competitive, delivers a seamless user experience, and meets evolving business requirements.
Future‑Proof Mobile Applications
Legacy app migration
Older applications often struggle with performance issues, security vulnerabilities, and outdated technologies. We migrate legacy apps to modern platforms, refactor code, and optimise architectures to ensure long‑term viability. Our migration strategies minimise downtime and enhance scalability.
App performance optimisation
Performance bottlenecks reduce user retention and engagement. Our team analyses and optimises app performance to improve load times, responsiveness, and efficiency. We simplify back-end tasks, use caching, and adjust database queries for smooth operation.
Security and compliance enhancements
Outdated security measures expose applications to risk. We upgrade authentication, encrypt sensitive data, and implement compliance‑driven security standards to protect users and maintain regulatory adherence.
Re‑architecture and refactoring
We stabilise and streamline ageing codebases by untangling dependencies, reducing technical debt, and introducing clear domain boundaries. We refactor hot paths, use modular patterns, and improve data access. This boosts performance and maintainability without needing a risky rewrite.
UI/UX overhaul and responsive design
We refresh interfaces to meet modern accessibility and usability standards, improving navigation, readability, and touch targets. Responsive layouts, adaptive typography, and inclusive design keep the experience steady on phones, tablets, and foldables. This leads to better task completion and retention.
Performance optimisation and telemetry
We diagnose cold starts, jank, and network latency, then apply pragmatic fixes: caching, batching, image strategy, offline support, and query tuning. Real‑time telemetry (metrics, logs, traces) and alerting ensure regressions are caught before users feel them.
Cloud migration and integration
We move from brittle hosting to resilient, observable cloud platforms. This includes containerisation, automated CI/CD, secrets management, and cost‑aware autoscaling. Event‑driven integrations and well‑documented APIs replace fragile point‑to‑point links, improving reliability and time‑to‑change.
Platform and OS upgrades
We upgrade SDKs, dependencies, and OS targets for iOS and Android, deprecating legacy APIs and introducing modern capabilities (push, background tasks, biometrics). Rigorous compatibility testing and phased rollouts reduce crash rates and keep your app compliant with store policies.
Security hardening and compliance
We strengthen authentication, adopt least‑privilege authorisation, and encrypt sensitive data at rest and in transit. Policy‑as‑code, dependency scanning, and regular security reviews align with regulatory requirements while preserving a smooth user experience.
Tailored App Modernisation Strategies
Ageing tech stacks limit innovation. We assess your application’s current technologies and recommend the right frameworks, libraries, and cloud‑based solutions. Our upgrades improve stability, maintainability, and performance.
User expectations evolve rapidly. We redesign interfaces to improve accessibility, navigation, and aesthetics. Our UX research ensures modernised apps are intuitive, inclusive, and engaging.
Cloud‑based applications offer flexibility and cost efficiency. We migrate monoliths to microservices‑based architectures, enabling better resource utilisation, improved scalability, and easier maintenance.
We evaluate your app’s structure, business needs, and user behaviour. Our assessment helps define a custom modernisation strategy that aligns with your objectives.
Planning
Analysis
Rigorous testing guarantees reliability, security, and performance. Our user experience research ensures your updated app meets modern usability standards.
Testing
UX Research
Our experts update ageing codebases, implement new features, and integrate modern technologies. We ensure a smooth transition while maintaining data integrity and app stability.
Design
Development
We deploy the modernised application with minimal disruption. Our team provides continuous support, monitoring, and performance optimisation to keep your app competitive.
Launch
Support
Case: Car‑sharing app rebuilt for speed
A transport start‑up needed to launch a new car‑sharing service fast. We proposed a PWA to maximise reach and reduce time‑to‑market. After rapid analysis and prototyping, we delivered an MVP in four months, then shipped the production release five months later.
The modernised architecture balanced cost, reliability, and iteration speed – enabling the team to validate demand, onboard early users, and scale features without rework.
Why WislaCode?
We use an evidence-based plan from discovery to rollout. This approach reduces risk, speeds up time-to-value, and prevents scope creep. We set clear acceptance criteria and show progress with demos in each sprint.
Proven Modernisation Playbook
We choose re‑platforming, refactoring, or targeted re‑writes based on ROI, not fashion. The result is a maintainable codebase and predictable total cost of ownership.
Pragmatic, not dogmatic
We treat performance, security, and accessibility as first‑class features. Code quality gates, automated tests, and observability are built into the pipeline so quality doesn’t get bolted on later.
Engineering done right
You keep the IP and the knowledge. We provide runbooks, architecture notes, and workshops so your team can operate confidently after launch.
Partnership and handover
FAQ About App Modernisation
A structured assessment guides the decision. We measure current stability, crash rates, performance hotspots, and dependency risks. Map the business‑critical journeys and estimate the cost of change. If most issues are localised, refactoring and selective re‑architecture pay back fastest. If the runtime, database, or hosting platform is the bottleneck, re‑platforming to a modern, observable stack is often best. A full rebuild is only for cases where key issues stop progress. These can include an unmaintainable monolith, outdated frameworks, or security risks. We model effort, risk, and expected gains (performance, reliability, development speed) to recommend the smallest viable change that delivers the required outcomes. This approach reduces technical debt while keeping velocity high.
We start with telemetry to find the real bottlenecks – cold starts, main‑thread blocks, chatty APIs, oversized images, or unindexed queries. Fixes target these root causes: lazy‑load non‑critical modules, batch network calls, cache smartly with sensible TTLs, compress and resize media, and enable HTTP/2/3. On device, we offload heavy work to background threads, schedule tasks when on Wi‑Fi/charging where appropriate, and add offline support to reduce retries. Server‑side, we tune queries, add pagination, and use CDNs for static assets. We lock in improvements with budgets and alerts, like startup time, frame stability, and payload size. This way, the app feels fast while also respecting battery and data limits.
Security is integrated into delivery. We adopt strong authentication (including biometrics where relevant) and least‑privilege authorisation. The central team manages secrets; they encrypt data in transit and at rest; and they maintain audit trails for sensitive actions. Pipelines enforce policy‑as‑code with dependency scanning, SAST/DAST, and container/image checks. We schedule regular penetration testing and review third‑party SDKs for data access. Compliance (privacy, consent, retention) is documented and tested, with clear user notices. Observability and anomaly detection help us respond quickly, while playbooks shorten incident MTTR. This keeps posture strong as features and integrations grow.
Discovery and planning usually take 2–4 weeks, leading into phased delivery. A focused refactor takes about 6 to 10 weeks. In contrast, broader re-platforming or cloud migration usually lasts 3 to 6 months. This depends on factors like integrations, data migrations, and non-functional requirements. Key drivers are integration access and quality, complexity of the codebase, test coverage, team availability, and the depth of performance, accessibility, and security work. We time-box outcomes for each phase and deliver in increments. This way, benefits come early. For instance, we see performance and crash-rate improvements before making bigger architectural changes. Transparent metrics and demos reduce uncertainty and help stakeholders make informed trade‑offs.
We maintain a compatibility matrix and upgrade in small, reversible steps. Feature flags isolate risky changes; canary and staged rollouts limit blast radius. Automated tests cover critical journeys, including background tasks, notifications, and permissions. We replace deprecated APIs, review platform behaviour changes, and validate on a realistic device and OS version set, including low‑end hardware. Third‑party libraries are audited for licence and security concerns. Monitoring (crash‑free sessions, ANRs, latency) is watched closely post‑release. This method keeps the store pipeline moving while protecting user experience.
We set baselines and target metrics before work begins. Common signals include performance (cold start, frame stability, API latency), reliability (crash rate, ANR rate), user experience (task completion time, retention, satisfaction), and delivery velocity (lead time, change failure rate). Commercial outcomes may include conversion, average order value, or support ticket reductions. We attribute improvements to releases where possible and track cohort behaviour to avoid false positives. The aim is a measurable lift in user satisfaction and business KPIs, paired with a lower cost‑to‑change thanks to improved architecture, tests, and automation.
Viacheslav Kostin, CEO
20+ years of experience in managerial positions in IT and banking.
Viacheslav Kostin, CEO
Previous roles: CEO in IT, Director of Strategy and Marketing in Banking, Curator of Holding Banks, Head of Products and Project Office.
Education: MBA for Executives at IMD (Switzerland), Leading Digital Business Transformation (IMD). Provides consulting in strategy and digital transformation.
Vasil Pahomov, CTO
20+ years of experience as a developer, analyst, and solutions architect.
Vasil Pahomov, CTO
Designs resilient, high-load systems with multiple integrations for banks and financial institutions. Expertise in distributed storage and microservices architecture.