Native & Cross-Platform Experts

Mobile App Development CompanyiOS & Android Apps That Users Love

Create engaging mobile experiences that captivate users. Our expert team builds native and cross-platform mobile apps that scale, perform, and delight on iOS and Android.

100+Apps Launched
4.8★Average App Rating
2M+Downloads Driven
Why Choose Us

Why Build Your App With Kosi Digital

We combine mobile expertise with user-centric design to create apps that stand out in the App Store and Play Store

📱

Native & Cross-Platform

Build native iOS (Swift), Android (Kotlin), or cross-platform (React Native, Flutter) apps based on your needs and budget.

🎨

Stunning UI/UX Design

Beautiful, intuitive interfaces following Apple and Material Design guidelines. Every interaction delights users.

Performance Optimized

Lightning-fast apps with smooth animations, optimized battery usage, and minimal storage footprint.

🔔

Push Notifications

Engage users with smart push notifications, in-app messaging, and deep linking strategies that drive retention.

🔄

Offline Mode

Apps that work seamlessly offline with smart data syncing, ensuring great UX even without connectivity.

🚀

App Store Success

Complete App Store and Play Store submission, optimization, and ongoing support to maximize downloads.

🗺️Our Process

From Idea to App Store Success

Our proven mobile development process ensures your app delights users and achieves business goals

1

Strategy & Planning

Define your app's purpose, target users, and key features. Analyze competitors and create a comprehensive mobile strategy.

Deliverables: User personas, feature roadmap, platform selection, monetization strategy
2

UX/UI Design

Design stunning interfaces that users love. Create interactive prototypes following iOS and Android design guidelines.

Deliverables: Wireframes, high-fidelity mockups, interactive prototypes, design system
3

Development & Integration

Build your app with clean, maintainable code. Integrate APIs, databases, payment gateways, and third-party services.

Deliverables: Working app builds, API documentation, admin panel, push notification setup
4

Testing & QA

Rigorous testing across devices, iOS versions, and Android versions. Performance testing, security audits, and usability testing.

Deliverables: TestFlight/Beta builds, QA reports, performance metrics, bug fixes
5

Launch & Growth

App Store submission, ASO optimization, marketing support. Post-launch analytics, user feedback integration, and updates.

Deliverables: Live app, ASO strategy, analytics dashboard, ongoing support
Technology Stack

Mobile Technologies We Excel In

Native and cross-platform frameworks that power world-class mobile applications

Native iOS

🍎Swift
📱SwiftUI
🎨UIKit
🔔APNs
☁️CloudKit

Native Android

🤖Kotlin
🎨Jetpack Compose
📐Material Design
🔔FCM
Android Studio

Cross-Platform

⚛️React Native
💙Flutter
📱Expo
🔄React Navigation
🎨NativeBase

Backend & Services

🔥Firebase
☁️AWS Amplify
⚙️GraphQL
🔐Auth0
💳Stripe Mobile SDK
💼Portfolio

Featured Mobile Apps

Explore mobile apps we've built that users love and businesses rely on

🏋️

Fitness Tracking App

Social fitness app with workout tracking, real-time stats, and community features. 500K+ downloads with 4.7★ rating.

React NativeFirebaseiOS & Android
🍕

Food Delivery Platform

On-demand food ordering app with real-time tracking, payment integration, and restaurant management system.

FlutterNode.jsStripe
💰

FinTech Banking App

Secure banking app with biometric authentication, transaction tracking, and investment management features.

SwiftKotlinBank-grade Security
💰Pricing

Mobile App Development Packages

Flexible pricing for startups to enterprises

MVP Launch

Custom-scoped

Test your idea fast

  • Single platform (iOS or Android)
  • Up to 8 key features
  • User authentication
  • Push notifications
  • Backend API
  • App Store submission
  • 60 days support
Get Started

Enterprise Scale

Custom

For complex apps

  • Everything in Full-Featured
  • Native iOS + Android apps
  • Unlimited features
  • Microservices backend
  • Advanced security
  • Dedicated team
  • Priority support
  • SLA guarantee
Contact Sales
FAQ

Frequently Asked Questions

Q: How much does it cost to develop a mobile app?
A: Mobile app cost scales with the number of platforms (iOS, Android, or both), feature count, backend and third-party integrations, offline support, and store submission requirements. A single-platform MVP is a very different engagement from a cross-platform enterprise app with native modules. Book a free consultation and we will scope your app and give you a detailed fixed estimate — no obligation.
Q: How long does mobile app development take?
A: An MVP app typically takes 8-12 weeks from kickoff to store submission. Full-featured apps with offline mode, payments, and integrations run 4-6 months, and enterprise apps 6-12 months. You get TestFlight or beta builds throughout, not just at the end.
Q: Should I build a native app or a cross-platform app?
A: Cross-platform (React Native or Flutter) is the right call for roughly 80% of apps: one codebase for iOS and Android cuts cost and timeline by about 40% while delivering near-native performance. Go native (Swift/Kotlin) when you need heavy graphics, AR, intensive background processing, or platform-specific hardware features. We build both, so the recommendation follows your requirements rather than a single framework we sell.
Q: React Native or Flutter — which is better for my app?
A: React Native wins when you have or plan a React web app (shared logic, one JavaScript team, easier hiring); Flutter wins for highly custom, animation-heavy UIs that must look identical on both platforms. Both are production-proven — we choose based on your existing stack, team, and design ambitions, and we put the reasoning in writing before you commit.
Q: What happens first when we start a mobile app project?
A: A strategy and planning phase: we define target users, prioritize features, choose the platform approach, and map the monetization model. You receive user personas, a feature roadmap, and a fixed quote — and the technical plan is reviewed by our principal architect before design begins.
Q: Do you build the backend and APIs for the mobile app too?
A: Yes — most apps we ship include a Node.js/NestJS backend, database (PostgreSQL or MongoDB), push notification infrastructure, and an admin panel, all from one team. Fifteen years of Node.js backend experience means the API is designed for mobile realities: flaky networks, offline sync, and battery-efficient polling.
Q: Do you handle App Store and Play Store submission?
A: Yes, end to end: developer account setup, store listings, screenshots, ASO keywords, privacy declarations, and shepherding the app through Apple and Google review, including responding to rejections. Post-launch, we manage version releases and staged rollouts so updates reach users safely.
Q: Who will be working on my app?
A: A typical team is an architect, 2 mobile engineers, a backend engineer, and a QA engineer testing on real devices. We are remote-first, headquartered in New Delhi, and every app is architect-reviewed before release under our Guardian model, led by founder Deepak Kumar Jha, a Technical Lead.
Q: How do you communicate with clients in the US, Europe, or the Middle East?
A: We keep daily working-hours overlap with US EST/PST, UK GMT, EU CET, and UAE GST, and we ship apps for clients across the US, UK, Europe, Dubai, Australia, and Canada. You get a dedicated Slack channel, builds you can install every sprint, and a demo call every two weeks.
Q: Who owns the app code and the store accounts?
A: You do — 100% of the source code and IP transfers to you, and we set up the Apple and Google developer accounts in your name from the start so your app listing is never hostage to a vendor. NDAs are standard before we discuss your idea.
Q: What does app maintenance cost after launch?
A: Launch tiers include 60-90 days of support for bug fixes and crash triage. After that, monthly maintenance plans cover OS compatibility updates (annual iOS/Android releases regularly break unmaintained apps), dependency upgrades, monitoring, and small features — most clients budget 15-20% of the original build cost per year.
Q: Is it better to hire a freelancer or an agency to build an app?
A: A freelancer can build a prototype, but a store-ready app needs design, backend, QA across dozens of devices, and store compliance — skills that rarely live in one person. Agency delivery also survives illness and vacations, and our work is architect-reviewed with a documented handover, which matters when you later raise funding or hire an in-house team.
Q: Can you build offline mode and push notifications?
A: Yes, both are core to retention and we treat them as first-class features: local storage with conflict-safe sync for offline use, and segmented push campaigns via FCM/APNs with deep linking into specific screens. We design the data layer for offline from the start, because bolting it on later usually forces a rewrite.
Q: How do you secure a mobile app that handles payments or sensitive data?
A: Biometric authentication, encrypted local storage, certificate pinning, and tokenized payments through Stripe or the platform pay SDKs — card data never touches your servers. We have shipped fintech apps that passed bank security audits on the first attempt, and we follow OWASP Mobile Top 10 throughout development.

Ready to Launch Your Mobile App?

Turn your app idea into reality. Schedule a free consultation to discuss your project and get a detailed estimate.

No commitment required • Architecture review included • Response within 4 business hours