Mobile App Development Process: From Idea to Launch in 90 Days

Have a brilliant app idea but don't know where to start? Building a mobile app isn't magic—it's a systematic process. Understanding each phase helps you set realistic expectations, avoid costly mistakes, and launch successfully within 90 days.

The 90-Day App Development Timeline

Week 1-2: Planning & Strategy (10 days)
Week 3-4: Design (10 days)
Week 5-10: Development (40 days)
Week 11-12: Testing (15 days)
Week 13: Launch Preparation (7 days)
Week 14: Launch & Monitoring (8 days)
Total: 90 days (approximately 3 months)

Note: Timeline assumes clear requirements and medium-complexity app. Complex apps need 4-6 months.

Phase 1: Planning & Strategy (Days 1-10)

Step 1: Define Your App Concept

Transform your idea into a concrete plan:

Questions to Answer:

• What problem does your app solve?
• Who is your target audience?
• What makes it different from competitors?
• What's the core value proposition?

Deliverable: One-page app concept document

Step 2: Market Research

Understand your competition and market:

Research Checklist:
□ Analyze 5-10 competitor apps
□ Identify gaps in market
□ Define unique selling points
□ Determine pricing strategy
□ Validate demand (surveys, interviews)

Step 3: Define Features and MVP

List all desired features, then prioritize ruthlessly:

Feature Priority Framework:

Must-Have (MVP):
- User registration/login
- Core functionality
- Basic profile management

Should-Have (Phase 2):
- Social sharing
- Advanced filters
- Notifications

Nice-to-Have (Phase 3):
- AI recommendations
- Advanced analytics
- Premium features

Pro Tip: Launch with 20-30% of all planned features. Add more based on user feedback.

Step 4: Choose Technology Stack

Based on requirements, budget, and timeline:

Decision Matrix:

Budget < $40,000 + Need Speed = Cross-Platform (React Native/Flutter)
Budget > $80,000 + Premium UX = Native (iOS & Android)
Simple Content App + Low Budget = Hybrid

Step 5: Create Project Roadmap

Break project into milestones with deadlines:

Example Roadmap:
Week 1-2: Planning complete
Week 4: Design approved
Week 10: Development complete
Week 12: Testing done
Week 13: App store submissions
Week 14: Launch

Deliverables: Technical specification document, feature list, timeline, budget breakdown

Phase 2: Design (Days 11-20)

Step 1: Create Wireframes

Low-fidelity sketches of every screen:

Purpose:

• Map user flows
• Define screen layouts
• Identify navigation structure
• No colors or detailed design yet

Tools: Figma, Sketch, Adobe XD, or even paper sketches

Output: 15-30 wireframe screens showing app structure

Step 2: Design User Interface (UI)

Transform wireframes into beautiful interfaces:

Design Elements:

• Color scheme (brand colors)
• Typography (fonts, sizes)
• Icons and imagery
• Buttons and interactive elements
• Loading states and animations

Platform Guidelines:

• iOS: Human Interface Guidelines
• Android: Material Design principles

Step 3: Create Interactive Prototype

Build clickable prototype for testing:

Benefits:

• Test user flows before coding
• Identify usability issues early
• Get stakeholder approval
• Guide developers precisely

Tools: Figma, InVision, Marvel, Principle

Step 4: Design Iteration Based on Feedback

Review with stakeholders and potential users:

Feedback Loop:
Present prototype → Gather feedback → Make changes → Review again
Typical iterations: 2-3 rounds

Deliverables: Final UI designs (50-100 screens), interactive prototype, design system, asset files

Phase 3: Development (Days 21-60)

Step 1: Setup Development Environment

Establish infrastructure and tools:

Technical Setup:

• Version control (Git/GitHub)
• Development servers
• Backend infrastructure (AWS/Firebase)
• CI/CD pipelines
• Project management tools

Step 2: Backend Development

Build server-side logic and database:

Backend Components:

Database Design:
- User tables
- Content/data tables
- Relationships and indexes

API Development:
- Authentication endpoints
- CRUD operations
- Business logic
- Third-party integrations

Server Setup:
- Cloud hosting (AWS, Google Cloud)
- Database (PostgreSQL, MongoDB)
- File storage (S3, Firebase Storage)

Timeline: 15-20 days parallel with frontend

Step 3: Frontend Development

Build the mobile app interface:

Development Sprints (2-week cycles):

Sprint 1 (Days 21-34):

• Authentication screens
• Main navigation
• Core feature screens
• Basic functionality

Sprint 2 (Days 35-48):

• Remaining features
• API integrations
• Push notifications
• In-app purchases (if needed)

Sprint 3 (Days 49-60):

• Polish and refinements
• Performance optimization
• Bug fixes
• Edge case handling

Step 4: Third-Party Integrations

Connect external services:

Common Integrations:

Payment: Stripe, PayPal, Apple Pay, Google Pay
Analytics: Google Analytics, Mixpanel, Amplitude
Push Notifications: Firebase Cloud Messaging, OneSignal
Social Login: Facebook, Google, Apple Sign In
Maps: Google Maps, Mapbox
Storage: AWS S3, Cloudinary

Step 5: Progress Reviews

Weekly demos and feedback sessions:

Weekly Review Checklist:
□ Demo completed features
□ Discuss blockers
□ Adjust timeline if needed
□ Approve before next sprint

Deliverables: Functional app (both iOS and Android if cross-platform), API documentation, admin panel

Phase 4: Testing (Days 61-75)

Step 1: Functional Testing

Verify every feature works correctly:

Test Cases:

• User registration and login
• All button clicks and navigation
• Form submissions
• Data display and updates
• Error handling

Method: Manual testing by QA team

Step 2: Compatibility Testing

Test across devices and OS versions:

Device Matrix:
iOS: iPhone 13, 14, 15 + iPad
Android: Samsung Galaxy, Pixel, OnePlus
OS Versions: Last 3 major releases

Network Conditions:
- WiFi
- 4G/5G
- Slow connection
- Offline mode

Step 3: Performance Testing

Measure app speed and resource usage:

Metrics:

• App launch time (< 2 seconds)
• Screen transition speed
• API response times
• Memory usage
• Battery consumption

Tools: Xcode Instruments (iOS), Android Profiler

Step 4: Security Testing

Identify vulnerabilities:

Security Checklist:
□ Data encryption (in transit and at rest)
□ Secure API authentication
□ Input validation
□ Secure storage of sensitive data
□ SSL certificate implementation
□ Third-party SDK security

Step 5: User Acceptance Testing (UAT)

Real users test the app:

Process:

• Recruit 10-20 beta testers
• Provide specific test scenarios
• Collect feedback via surveys
• Track bugs and suggestions
• Implement critical fixes

Tools: TestFlight (iOS), Google Play Beta (Android)

Deliverables: Bug reports, test results, approved app ready for submission

Phase 5: Launch Preparation (Days 76-82)

Step 1: App Store Assets

Create marketing materials:

Required Assets:

App Icon: Multiple sizes
Screenshots: 5-8 per platform
Preview Video: 15-30 seconds
App Description: Compelling copy
Keywords: SEO optimization (iOS)
Privacy Policy: Legal requirement
Support URL: Help documentation

Step 2: App Store Optimization (ASO)

Optimize for discoverability:

ASO Elements:

• App title (include main keyword)
• Subtitle/short description
• Keyword field (iOS) or description (Android)
• Compelling screenshots with text overlay
• Ratings and reviews strategy

Step 3: Create Landing Page

Build website for app marketing:

Landing Page Must-Haves:

• Clear value proposition
• App screenshots/video
• Feature highlights
• Download buttons (App Store, Google Play)
• Email capture for launch notification
• Social proof (if available)

Step 4: App Store Submissions

Submit to Apple and Google:

Apple App Store:

• Review time: 24-48 hours
• Strict guidelines
• Potential rejections (be prepared)

Google Play Store:

• Review time: Few hours to 1 day
• More lenient guidelines
• Faster approval process

Pro Tip: Submit to both stores simultaneously.

Deliverables: Approved apps in both stores (pending release), landing page live, marketing materials ready

Phase 6: Launch & Post-Launch (Days 83-90)

Step 1: Soft Launch

Release to limited audience first:

Benefits:

• Test with real users
• Identify critical bugs
• Gather initial feedback
• Refine before full launch

Approach: Launch in one country or to email list subscribers

Step 2: Monitor Closely

Track everything in first week:

Key Metrics:
- Downloads and installations
- Crash reports
- User engagement
- Feature usage
- Reviews and ratings
- Server performance

Tools: Firebase Analytics, Crashlytics, App Store Connect, Google Play Console

Step 3: Gather User Feedback

Actively collect user input:

Methods:

• In-app feedback forms
• App store reviews monitoring
• User surveys (email)
• Social media comments
• Support tickets analysis

Step 4: Quick Fixes

Address critical issues immediately:

Priority Fixes:

• App crashes
• Login/authentication issues
• Payment problems
• Major UX blockers

Timeline: Release hotfix within 24-48 hours if critical

Step 5: Marketing Push

Promote your app:

Launch Week Marketing:

• Email announcement to list
• Social media campaign
• Press release (if applicable)
• Reach out to app review sites
• Paid ads (Facebook, Google)
• Content marketing (blog posts)

Post-Launch: Continuous Improvement

Week 2-4:

• Analyze user behavior
• Prioritize feature requests
• Plan first update (bug fixes + small improvements)

Month 2-3:

• Release major update (new features)
• Implement user suggestions
• A/B test improvements
• Expand marketing efforts

Ongoing:

• Monthly app updates
• Regular content additions
• Performance optimization
• Security updates

CentoSquare's 90-Day App Development

At CentoSquare, we follow this proven process for rapid, quality app delivery:

Our Advantage:

• Fixed 90-day timeline for MVP
• Weekly progress demos
• Transparent communication
• Experienced team (no learning curve)
• Post-launch support included

What We Deliver in 90 Days:

• Fully functional app (iOS + Android)
• Admin panel/dashboard
• Backend API
• App store submissions
• 30 days post-launch support
• Source code ownership

Typical 90-Day MVP Cost: $30,000 - $80,000

Success Rate: 90%+ of projects launch on time

Conclusion

Building a mobile app in 90 days is achievable with proper planning, clear requirements, and experienced developers. Follow this systematic process: plan strategically (10 days), design thoughtfully (10 days), develop efficiently (40 days), test thoroughly (15 days), and launch confidently (15 days).

Key to Success: Start with MVP, launch quickly, iterate based on user feedback.

Ready to start your 90-day app journey? At CentoSquare, we've launched 200+ apps using this proven process. Let's turn your idea into reality.

Start Your 90-Day App Development →