Many businesses budget carefully for mobile app development but dramatically underestimate the cost of maintaining it after launch. Industry benchmarks suggest that annual maintenance costs 15 to 25 percent of the original development cost — and that does not include feature additions or major updates. Understanding these costs upfront helps you budget realistically and avoid the trap of launching an app you cannot afford to keep running.
The Four Categories of App Maintenance Cost
1. Infrastructure and Hosting
Your app needs a backend — servers, databases, file storage, push notification services, and potentially a CDN. For small to medium apps, cloud hosting costs typically range from 100 to 500 euros per month. As your user base grows, so do your infrastructure costs. Apps with heavy media content, real-time features, or large data processing needs can cost significantly more.
- Cloud hosting (AWS, Google Cloud, Azure): 100–500 euros per month for SME apps
- Push notification services: 0–100 euros per month depending on volume
- CDN for media delivery: 20–200 euros per month
- SSL certificates and domain renewal: 50–200 euros per year
- Database hosting and backups: included in cloud hosting or 50–300 euros per month separately
2. OS Updates and Compatibility
Apple and Google release major OS updates annually, and both platforms regularly deprecate APIs and change design guidelines. Each year, your app needs to be tested and updated for compatibility with the latest iOS and Android versions. Failing to do this results in crashes, visual glitches, and eventually removal from app stores. Budget for 20 to 60 hours of developer time annually for OS compatibility updates.
3. Bug Fixes and Performance Monitoring
No matter how thorough your testing was before launch, real users will find bugs — especially on devices and OS versions that were not part of your test matrix. You need crash monitoring (tools like Firebase Crashlytics or Sentry), performance monitoring, and a budget for fixing critical issues as they arise. A retainer of 10 to 20 hours per month covers ongoing bug fixes for most SME apps.
4. Third-Party Service Updates
If your app integrates with payment providers, maps, social login, analytics, or other third-party services, those services update their APIs and SDKs regularly. Breaking changes can cause features to stop working overnight. Keeping integrations current requires ongoing developer attention.
Annual Maintenance Cost Estimates
Based on our experience maintaining apps across industries, here are realistic annual maintenance budgets for apps built in Romania:
- Simple app (utility, informational): 3,000–8,000 euros per year
- Medium app (e-commerce, service booking): 8,000–20,000 euros per year
- Complex app (real-time features, multiple integrations): 20,000–50,000 euros per year
Rule of thumb: budget 20 percent of your original development cost per year for maintenance. If your app cost 40,000 euros to build, expect to spend approximately 8,000 euros per year to keep it running smoothly.
How to Reduce Maintenance Costs
- Choose cross-platform (React Native or Flutter) to maintain one codebase instead of two
- Use managed backend services (Firebase, Supabase) to reduce infrastructure management overhead
- Write comprehensive automated tests during development to catch regressions early
- Design a modular architecture so updates to one feature do not break others
- Establish a maintenance retainer with your development partner for predictable monthly costs
OBI Systems offers transparent maintenance retainer packages for all apps we build, including OS compatibility updates, bug fixes, security patches, and infrastructure monitoring. We also maintain apps built by other teams — starting with a comprehensive code audit and transition plan.