Launching an app is just the beginning, the real challenge is sustaining its growth. According to some research an average app loses almost 77% of its daily active users within just three days of its installation. The major cause is poor performance, although that may not be the only issue. Users will rarely return to an app should it start crashing or become slow or unresponsive as more users use it. There is a solution, and that’s scalability. This is an architectural approach that ensures an application can manage user growth without compromising its performance.
This means building for scale, at the very start is a strategic necessity. A single hour of downtime for a large enterprise can cost $300,000 and more, as reported in a 2024 survey by ITIC. This is detrimental to growth, can destroy user trust, and cripple momentum. It, therefore, becomes absolutely vital to understand and implement key app scalability best practices for long-term success. And partnering with expert scalable app development services will ensure the right foundation is laid.
The Core Principles of Scalable Architecture
Scalability is a result of deliberate design choices. When creating an app, the system must be designed to ‘gracefully’ adapt to increased demand. In simple terms, it means the app should be able to handle ten thousand users or ten million without issue. Here are the foundational pillars for achieving it:
1. Adopt a Microservices Architecture
Historically, applications were built as single, monolithic units. This is a rigid approach and it means scaling one part, would require the entire application to be scaled. This is both inefficient and unnecessarily complex. The modern solution is a microservices architecture which involves breaking down an application into a collection of smaller, independent services. Each service handles a specific business function and can be developed, deployed, and scaled separately.
According to Straits Research, the global microservices architecture market is projected to grow to $11.8 billion by 2032, a clear indication that it is, indeed, a core tenet of modern software development. In this model, should one service fail, it doesn’t affect the entire application allowing development teams to work on different components simultaneously, thus speeding up updates.
2. Leverage Cloud Platforms for Elasticity
Today, there’s no longer a need to rely on fixed, on-premise servers for growth. Cloud platforms like AWS, Google Cloud, and Azure are the bedrock of scalability. These services offer tools that provide elasticity, i.e. the ability for infrastructure to auto-expand or contract based on demand.
- Auto-Scaling: Automatically adjusts computing resources based on real-time traffic on the app, ensuring performance doesn’t wane during peak loads while simultaneously saving costs during quiet periods.
- Load Balancing: Distributes incoming traffic across multiple servers, preventing any single server from becoming a bottleneck and improving stability.
3. Implement a Scalable Database Strategy
An application’s database is often the first component to buckle under pressure. As the user base grows, so does the volume of data. A traditional single-server SQL database can quickly become a bottleneck. Effective app scalability best practices for databases include:
- Choosing the Right Database: While SQL databases are excellent for structured data, NoSQL databases (MongoDB or Cassandra) are often better suited for the large volumes of unstructured data, which is common in modern apps and are designed for horizontal scaling.
- Database Sharding: This involves splitting a large database into smaller, faster, more manageable parts called shards. Each shard can be hosted on a separate server, effectively distributing the load.
- Read Replicas: Creating read-only copies of the database can offload read requests from the primary database, improving performance for read-heavy applications.
4. Optimise Delivery with Caching and CDNs
Speed is critical for user retention. A key strategy for building high-performance apps is to reduce latency by bringing data closer to the user. This is achieved through caching and Content Delivery Networks (CDNs).
These networks store copies of your content on servers worldwide. When a user requests a file, it’s delivered from the server closest to them, dramatically reducing load times and taking pressure off the core application servers.
5. Prioritise Continuous Performance Monitoring
Scalability should not be a one-time setup, and it must be monitored vigilantly. Implementing robust monitoring and analytics tools is crucial for building high-performance apps. These tools help track key metrics that include server response times, error rates, and resource utilisation. When performance degradation is discovered early, developers can proactively address issues before they start to impact the user experience. Gartner predicts that by 2025, over 95% of new digital initiatives will be built on cloud-native platforms, where continuous monitoring is a key practice.
Conclusion
Building a scalable application is a proactive investment in its growth. A strategic approach that prioritises flexible architecture, cloud infrastructure, and a resilient data layer from the outset is key. By adhering to these app scalability best practices, developers can create a robust foundation that supports user growth. Given that this is a complex task, organisations should turn to specialised scalable app development services to ensure their application is not just built for today, but engineered for the boom of tomorrow.