Application Scalability – Future-Proofing Your App for Long-Term Success

Imagine building a fintech or eCommerce application after studying users’ exact requirements, adding features that meet their expectations, and packing all the experience within an immersive design. Post the hard work and promotion you put in the success of the application, you launch it in the market.

Soon, you find that after the initial peak in app downloads, the numbers have started dwindling at a visible (slightly abnormal) rate. And after putting your software testing team to work, the reason surfaces – application scalability that is leading to app performance degradation issues.

The benefits of building scalable applications cannot be emphasized enough. An app – web or mobile – that is built with an scalability approach is known to help business with –

• A change-ready ecosystem
• Positive user experience
• Resource optimization-led cost savings
• Increased probability of high ROI 

In order to achieve this along with the many other benefits, it is critical to build your application to be scalable.

In this article we are going to look into the different facets of scalability in app development with the intent to help your app become future-proof.

But first thing first.

When Should You Start Worrying About App Scalability?

Scalability in mobile app development is about creating the capability to manage greater workload or user demand, such as high traffic, greater data storage, or higher computation requirements, without any compromise on the app performance.

But what are the warning signs that show it’s time to start acting?

• The performance issues are on a rise. Slow load times, timeouts becoming constant, or frequent system errors are indications that the app is struggling with heavy workload.
• Your resources are regularly operating at their peak capacity. An infrastructure operating at its very limits (for example, at maximum CPU, memory, storage, or network usage) can cause frequent downtime and dwindling performance.
• You have high traffic peaks and network latency. High latency at greate user loads could mean that the mobile or web application has outgrown its infrastructure abilities, causing service degradation.
• You’re scaling your business. If you are planning to introduce features or get into newer markets, app scaling becomes essential for meeting the growing demands and supporting the scale of business growth.

What Options Do You Have in Scaling Applications?

Now that you have decided it’s time to scale, let us look into the options you’ll have to go through.

1. Vertical Scaling

This is about giving your application a bigger architectural capability. Here, you will be boosting your server’s capacity with greater CPU power, storage, or memory. It’s ideal for small-sized apps, because it comes with limitations in infinite hardware upgrades.

2. Horizontal Scaling

Your app has a range of features where they share resources and operational load. This is one of the popular types of application scalability where you have to add servers or instances in your app, spreading the operational workaround. It’s deemed best for large-scaled apps having a large number of users, and you have to keep things running friction-less.

3. Microservices

Imagine your app as a puzzle, where every puzzle piece works as an individual service. Scaling mobile apps through microservices is about dividing your app into pieces, which you can scale depending on the part which you need.

4. Serverless

Imagine a scenario where you do not have to worry about app maintenance at all. The software works when you require it. That is what a serverless model of building a scalable web application is about. It directly handles scaling for your app. It’s considered cost-efficient and perfect for unpredictable workloads.

While we leave the choice between the different types of application scalability to you depending on what your application goals are, the ways to approach the activity are more or less the same.

Here are the different ways and tips you can apply for building scalable applications divided in web and mobile categories.

Tips for Building a Scalable Mobile Application

Scalability in app development can be introduced through a series of approaches. Here are a few of the ones we follow.

1. Scale Data Storage

One of the most difficult aspects of scalability in app development is database. The core challenge can be understood by looking into the CAP approach:

• Consistency – every read gets the most recent write or an error.
• Availability – every request gets a (non-error) response, without an assurance that it would have the most recent write.
• Partition tolerance – the system operates despite an arbitrary number of messages being dropped (or delayed) by the network in-between nodes.

You can only choose two of the above three points for a database system. For instance, if you value consistency and availability, you give up partition tolerance. As a result, your database system would yield a single node instance (potentially with fallbacks/read-only mirrors).

Before working on hardware, you must consider optimization of software. Usually, database queries and write operations can be easily optimized. This doesn’t just save money on the necessary hardware, but also enables the app to manage more users. Lastly, we recommend adding an effective cache layer to achieve more with less resources.

2. Scale File Storage

Like data storage, you should also plan for distributed file storage. While utilizing network-attached storage (NAS) or a storage area network (SAN) can prove helpful for the on-premise systems, you can also use cloud services.

Cloud providers have dedicated services for files management, including caching, geo-distribution, checks, fragmentation, and more, they also enable setting up of policies for file access.

A key thing to note here is that the cloud costs can become too expensive too quickly, especially when you are building mobile apps at scale, so ensure that you are calculating the expected bandwidth ahead of time in order to avoid surprises.

3. Optimize for Traffic

Even while the file and data storage have been made distributed and easy to scale, your app might not perform to its full capacity. This can happen because of a single entry point forming a bottleneck. There are two ways to handle this when planning for scalability in mobile app development.

DNS rotation removes the situation where only one IP receives all the requests going to the domain.

Another technique is load balancing like Kubernetes’ built-in load balancer for diverting traffic to multiple running events. This is also where cloud provider partnership is considered helpful. They have services which use load balancers. For example, in AWS, you can use Amazon Elastic Load Balancer for dividing all the incoming traffic.

4. Prepare for Newer Markets

When you are preparing for scalability in mobile app development to take your app beyond the current market, focus on localization, including language support through Unicode, cultural elements, and legalities. A successful market scaling approach would also involve performing local market research, following compliance with local regulations like GDPR.

Moreover, to make sure that the static content gets delivered to users quickly, irrespective of the location, utilize CDN services. This can also help you lower latency and better the user experience.

5. Scale through Efficient Data Management

When building scalable applications, the primary intent is to manage the growing user base and the high volume of data that will come with it. You can handle this by implementing scalable database solutions like MongoDB or Cassandra which grows with your application and handles large datasets effectively.

You can also use database optimization approaches such as indexing, data sharding, etc to ensure fast access to datasets and maintenance of app performance.

6. Plan for Infrastructure Scalability

The infrastructure must handle growth minus performance degradation. This is where it is advised to use cloud-based solutions like Google Cloud’s Compute Engine or AWS Elastic Compute Cloud (EC2) – they promise on-demand scalability for managing the growing load.

Also, during this phase of scaling mobile apps, techniques such as orchestration with Kubernetes and containerization with Docker can be implemented, which would lead to smooth scaling of services and effective resource usage.

7. Know Your User Base

The last critical factor to note when scaling mobile apps is to have a deep understanding of the user base – their app usage patterns, time of peaks, favorite/frequently used features, and challenges that they. Gather this set of information through surveys, analytics tools, and feedback.

These user-centric data points would help with informing which features should be prioritized when scaling mobile apps and ensure that the software is aligned with the users’ evolving requirements.

Tips for Building a Scalable Web Application

Scalability in web applications is influenced by a range of factors –

• Design and architecture
• Resources and infrastructure
• Traffic patterns and user behavior
• APIs and other third-party services
• Code effectiveness and optimization.

The ways to ensure it happens perfectly calls for applying a series of tips.

1. Select the Best Hardware

Hardware selection sets the foundation of the web application. Companies must go with resources which can back expansion of distributed database services over a period of time.

The hardware you choose should have clear indications of key metrics, like percentage of memory and CPU utilization – an information set that would help determine the need for scalability at any stage.

2. Opt for Microservices Architecture

Monolithic applications tend to be tightly coupled and contain a large code base that can get complex. The architecture also limits scaling of single components as and when needed without affecting the entire application. Moreover, scaling applications built over monolithic architecture can be a costly affair.

Using microservices architecture enables scaling of only necessary web elements by the application’s codebase getting divided into independent modules to match the workload requirements.

[Also Read: Serverless Vs Microservices – Which Architecture should Businesses Choose?]

3. Introduce Caching in the System

Data-heavy web applications tend to limit performance. A solution to this can be caching. A cache stores data for a brief period so that all the future requests made for the data can be served faster to the client, removing the reliance on connecting and querying the database when the client requests something. This is also effective when scaling read-intensive web applications, as it lowers the total query time and provides faster data access.

When selecting a caching strategy, it’s critical to make sure that it aligns with the nature of data. For example, if the data changes frequently, the strategy should be consistent with the database updates like using a content delivery network (CDN) for static assets such as images and HTML.

4. Use Load Balancers

Another strategy for scaling web applications can be to implement load balancers. The approach optimizes traffic distribution through strategic routing of the incoming requests towards multiple servers for fast processing.

5. Select the Right Database

Database is an integral part of any web application scalability process. The choice and definition of ‘correct database’ depends entirely on the data type the business needs to save and store.

For reference, at Appinventiv when we work on relational data, we suggest choosing either Microsoft SQL, MySQL, or PostgreSQL, while for the unstructured data usage, the suggestions look like NoSQL databases such as MariaDB or MongoDB.

[Also Read: MongoDB vs MySQL: Which Database is Better for Your Business]

6. Adopt an API-first Approach

The strategy makes APIs a modular and discrete part of web application development. It guarantees that the application’s functions can be completely accessed through an API. The process also eases scaling web applications, since the apps built from small disaggregated parts can efficiently scale by working on only the needed parts.

The API gateways tend to serve as a single entry point in the web application. It merges different requests coming in from the user and then routes them to their correct endpoints. The gateway then merges the outputs coming in from multiple requests before sending them to the end user, thus lowering the number of interactions between the web apps and its user.

7. Build Multi-tier Software Architecture

In this architecture, the web app gets divided in several tiers, such as the application server, web server, and database server. Each of the tiers then run individually on multiple hardware and servers, making the process of building a scalable web application easy.

Through the multi-tier software approach, you can also modify the server or hardware configuration for every tier without it impacting the other tiers’ performance. This also proves to be a cost-effective solution since the changes are only made on the affected tier.

What Challenges Can You Face when Building Scalable Applications? What are the Proposed Solutions?

Here are some challenges that you might encounter when planning scalability in mobile app development and the ways we solve them.

Unscalability of the Current Architecture

Apps built on a poorly designed or monolithic architecture depend on legacy technologies, and a tight coupling of components, which can prove difficult for implementing scalability in mobile app development without huge rework efforts.

The solution we follow here is migrating the software to microservices or a service-oriented architecture that enables easy deployment, scaling, and managing of independent app components.

Data Inconsistency

As an application processes more data, ensuring consistency becomes more challenging for scaling applications. This is especially true for distributed systems, where different versions of the same information can end up being stored on different servers. This results in outdated information and conflicting values.

To manage this, we implement efficient data synchronization approaches. Using the best database architectures, integrating distributed consensus protocols, and applying conflict resolution approaches are some ways we guarantee data consistency across every application component.

Resource Constraints

Restrictions in memory, computing power, storage, or network bandwidth tend to affect scalability in web applications. For example, less resources can lead to app performance degradation during peak usage time.

To avoid this, we continuously track the resource usage and optimize it in line with the demand. Additionally, we suggest investing in a well-provisioned and scalable cloud infrastructure as that offers greater flexibility in terms of resource allocation.

Security Vulnerabilities

In the journey of scaling web applications and mobile solutions, the system might get exposed to attacks and security breaches. With the software getting bigger, hackers might exploit the issues in the app’s code, data handling process, and infrastructure.

To prevent this, we follow different approaches –

• Secure coding practices
• Regular – timed and spontaneous – security assessments
• Rigorous penetration testing
• Strong authorization and authentication mechanisms
• Ensure every API and third-party software is updated for known vulnerabilities

These steps help protect your application and the users from potential cyber threats.

High Application Scalability Cost

Adopting a single or different method for scaling applications can inevitably add to licensing and subscription expenses. However, the amount of ignoring scalability in app development is much higher, since you risk over-provisioning of the resources and add on to unnecessary expenses and performance challenges.

To handle the costs efficiently, you should carefully strategize scaling on the basis of actual usage trends and modify it to balance the cost and performance efficiency.

Successfully rectifying these scalability-related roadblocks call for a comprehensive knowledge around app requirements and architecture, proactive planning, and continuous monitoring as the application grows. This is where partnering with a trusted software development company like Appinventiv, with a proven track record of building mobile apps at scale can make all the difference.

Here’s an example of how we helped a Fintech application scale.

A Canada-based Fintech startup reached out to us for web and mobile app development services. The short term goal for them was to raise funds from investors, for which they wanted to start with an MVP that would then be scaled based on hypothesis testing.

To achieve this, we built a scalable and strong architecture with the ability to handle huge traffic loads. Our development team built an MVP in a tight timeline of two weeks using Storybook and React Native. When the app started getting high attention and demand, we transitioned the complete backend to React, enabling easy code sharing between the website and the mobile application.

Today, the app has over 1 million downloads, with no sign of performance issues.

FAQs

Q. What is application scalability?

A. App scalability defines the capability of an application to manage increased workload or users demand without compromising on performance or reliability.

Q. Why build a scalable app?

A. Building scalable apps is crucial for multiple reasons:

• Handle Sudden Growth
• Maintain Performance
• Cost Efficiency
• Business’s Future-proofing
• Competitive Advantage

Q. How to scale an application?

A. The process of scaling applications differs in mobile and web platforms. When scaling web applications, you can consider opting for microservices architecture, using caches, selecting the right database, and adopting an API-first approach. In the case of mobile apps, you can opt for strategies like Scaling data and file storage, optimizing for traffic, scaling through efficient data management, and planning for infrastructure scalability.

THE AUTHOR

Sudeep Srivastava

Co-Founder and Director