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A Comprehensive Guide On Frontend Monitoring

If you’ve ever stepped away from a website only to return and find it loading slower than a snail on a stroll, you know how painful it can be. And you’re not alone. Research shows that 47 percent of consumers expect a web page to load in two seconds or less. Frontend monitoring tools can help you meet this expectation by tracking performance from the user’s perspective. This blog will explain the ins and outs of frontend monitoring, including the best practices and tools to help you get started.

Alerty's solution, frontend monitoring, can help you achieve your objectives, such as learning about frontend monitoring tools and best practices. The benefits are straightforward. You can figure out what's slowing down your website and how to fix it before your users get fed up and leave.

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Table of Contents

What Is Frontend Monitoring?

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Frontend monitoring is the process of tracking and maintaining the health of the presentation layer of your applications. It’s everything that a user would interact with, from the content and menu to APIs and other client-facing components.

Application performance monitoring, or APM, focuses on user experience rather than the communication between server and client. While both are worth monitoring, understanding how users interact with your application is crucial to delivering a good experience, which leads me to my next point.

With the help of frontend monitoring tools, you can monitor your apps easily and in detail. 

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What Are The Main Types Of Frontend Monitoring?

Woman Monitoring Code - Frontend Monitoring

Frontend monitoring lets you understand your website or application's performance from your users’ perspective. Users who interact with your site don’t care about your server or application performance. They care about how fast your site loads, how quickly they can navigate to the page they want, and whether any of the features on the page are broken.

Frontend monitoring gives you insight into the metrics that affect users’ experience. This information lets you improve performance and keep your users and business happy. 

The Two Main Types of Frontend Monitoring

Frontend monitoring is about monitoring how your website or app is performing from the user’s perspective. It generally falls into two main categories:

  • Proactive 
  • Reactive monitoring

Proactive Testing

Proactive monitoring is like having a test run before the big game. It involves techniques like synthetic monitoring and mobile application testing, where you simulate user interactions across different:

  • Browsers
  • Devices
  • APIs

Doing this lets you catch issues before they ever reach your users. It’s like checking the road for potholes before anyone drives on it—fixing potential problems before they can impact the real user experience.

Reactive Testing

Reactive monitoring kicks in once users interact with your application. This includes tools like Real User Monitoring (RUM) and session replay. Reactive monitoring captures real-time data on how users are experiencing your site or app, from performance metrics to specific user behaviors.

It’s like having a camera on the road, seeing where and when users encounter bumps or detours. This allows you to address those pain points and improve the overall experience.

Hybrid Monitoring

The best approach to front-end monitoring is a combination of both proactive and reactive methods. Using them together lets you prevent problems before they occur and gain valuable insights into unexpected issues your users face in real time.

This comprehensive strategy ensures your application runs smoothly and provides your users with the best possible experience.

Preventative Measures

Catch issues before they affect your users with Alerty's free APM solution today!

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How Does Frontend Monitoring Work?

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Frontend monitoring is all about keeping your website or app in top shape by understanding how it's performing from the user's perspective. It involves different tools and methods, each with its way of observing things.

Let's start with proactive monitoring, which uses synthetic tests. This method is like running a series of practice drills. It works by sending simulated requests to your app from various:

  • Browsers
  • Devices
  • Locations worldwide

The goal here is to see how everything responds under different conditions, allowing you to catch potential issues before real users ever experience them.

User Behavior Analysis

On the flip side, reactive monitoring is all about observing real users in action. This is where Real User Monitoring (RUM) comes into play. RUM captures how users interact with your app, recording everything from performance data like Core Web Vitals to any errors or long tasks.

It’s like having a live feed of your users’ experiences, helping you see how your app performs in real-world situations. Then there’s session replay, which takes things a step further. This tool lets you watch visual replays of your users’ browsing sessions to see where they might get into trouble.

Error Analysis

It’s beneficial for spotting and reproducing user errors, making troubleshooting much faster. When you combine this with backend metrics and traces, you can quickly pinpoint and fix the root cause of issues efficiently. Using synthetic tests and real user data, frontend monitoring provides a comprehensive view of your app’s health.

It’s not just about checking predetermined scenarios; it’s about understanding how your app performs in the hands of real users, ensuring a smoother and more reliable experience for everyone.

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Why Is Front End Monitoring Important?

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Continuous front-end monitoring helps you detect issues before they impact users. Instead of waiting for users to report a problem with your application, you can find and fix issues ike slow load times or broken features on your own. This proactive approach helps you maintain a consistently high level of performance.

Adapting to Changes: Stay Agile

As your application grows and evolves, adapting to changes becomes crucial. With new features, updates, and shifts in user behavior, you must stay agile. Continuous monitoring allows you to adjust smoothly, ensuring your application remains optimized and responsive, no matter how much it changes over time.

Data-Driven Improvements: Fine-Tune Your Application

Ongoing monitoring provides a steady stream of data, which can be used to make informed decisions about optimizations and enhancements. This data-driven approach allows you to fine-tune your application, improving both the user experience and overall performance.

Build User Trust: Foster Loyalty

When your application performs reliably, it helps to build user trust. Users are likelier to stay loyal to a brand that consistently delivers a smooth and reliable experience. By ensuring your front end is always performing at its best, you foster greater confidence and trust in your brand.

Stay Competitive: Keep Up with Industry Standards

Ongoing monitoring helps you stay competitive in a crowded market. With continuous insights into your front-end performance, you can keep your application on par with, or even ahead of, competitors. This ensures that your application meets the high standards users expect, helping you maintain a strong position in the market.

Front End Monitoring Tools

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Monitoring tools are essential software applications that help businesses closely monitor their computer systems and networks' performance, health, and security. These tools track various metrics, such as:

  • CPU load
  • Network bandwidth
  • Server services
  • Disk space, to ensure everything is running smoothly

The primary purpose of monitoring tools is to detect potential issues early, allowing administrators to address them before they escalate into significant problems that could impact users. For instance, if a server's CPU load is consistently high, a monitoring tool can alert the IT team, who can investigate and resolve the issue before it affects application performance.

Data-Driven Optimization

In addition to detecting problems, monitoring tools often provide real-time data and historical reports, helping businesses optimize their systems and plan for future needs. By continuously tracking key metrics, these tools play a vital role in maintaining the following:

  • Reliability
  • Efficiency
  • Security of IT environments

These tools can be grouped into different categories:

Website Monitoring

As a website is a combination of the frontend and backend services, website monitoring is a broad term that encompasses various other monitoring techniques, including:

  • Frontend monitoring
  • API monitoring and the like

Through website monitoring, you ensure that your website works as intended.

Error Prevention

You should ensure the website doesn’t cause any 5xx server errors. A well-formatted and functioning site map is also essential, as it allows search engine crawlers to index your website easily.

You can also monitor other aspects like uptime, responsiveness, forms, accessibility, etc. If any of these aspects fail the monitoring tests, the monitoring system notifies the support team, who can then take the required actions and fix the issues.

Feature Checklist

A good website monitoring tool should have the following features:

  • Some CDN nodes may go down sometimes if your website uses a CDN (content delivery network). So, monitoring your website in different regions is important, and you need to choose a tool that detects multiregional downtime.
  • Performance depends upon different metrics, such as bundle size and bandwidth, so your monitoring tool should be able to provide detailed performance measurements.
  • Most modern-day browsers block websites that don’t use HTTPS. Thus, your monitoring tool should also verify SSL certificates.
  • Pinging a website too often wastes resources, and if you ping after a long delay, you may miss out on an important event. Hence, a good tool should allow you to configure the request intervals according to your needs.

API Monitoring

API monitoring is used to monitor the uptime and correctness of the APIs. It can be implemented to monitor both:

  • REST APIs 
  • GraphQL APIs

While APIs work on the backend, they are integrated with the front end. If a front end is rendered based on the API’s response, then the API’s response time is a very important metric to monitor as it affects the front end's load time.

API Optimization

Some of the best practices related to implementing API monitoring include the following:

  • The tool allows you to specify custom data validation.
  • The tool allows you to configure request intervals.
  • The tool allows you to send custom HTTP headers and cookies.
  • The tool will cross-check from multiple probe locations before sending any alerts.

Real User Monitoring

Real user monitoring allows you to detect user-specific performance issues, JavaScript errors, and other device-specific issues by recording user sessions. Users’ browsers, geographic locations, and connection speeds vary significantly. These factors define your users’ experience and affect your website’s performance; this is precisely where accurate user monitoring comes into play.

One of the best practices to consider while implementing real user monitoring is tracking the performance of newly added features. New features are bound to break more often than existing ones. You should also track real user journeys through the application, as this helps you understand how end-users experience your website.

Frontend Error Logging

Logging the errors on the frontend is as important as logging those on the back end. Frontend are usually JavaScript errors that can make your UI a mess. In a React.js app, you may pass a string value to a prop that accepts a number value, which can cause problems in your mathematical calculations and result in errors.

You can wrap your code in a try-catch block and add a console.log statement in the catch or finally block to catch such errors. The console statement only logs the information in the user’s browser, which you don’t have access to, and this is where frontend error-logging tools can help you.

Error Logging

Frontend error-logging tools provide logs and other important information like:

  • Users’ browsers
  • Operating systems
  • Page URLs
  • Variable values
  • Other important data for debugging issues

A good frontend error-logging tool should at least have the following functions:

  • The tool should allow you to send JSON-formatted logs.
  • The tool should be able to capture and report all errors across your application, whether they originated within a framework like React or in your business logic.

Early Detection

Catch issues before they affect your users with Alerty's free APM solution today!

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Who Should Use Frontend Monitoring?

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Frontend monitoring tools benefit frontend and mobile developers at all stages of the development cycle. Here are a few of the specific ways that individual development teams can use these solutions:

Error Troubleshooting

Using real user monitoring and session replay, developers can easily troubleshoot frontend errors with full context. RUM gives you the details on what’s happening with your users in the wild, while session replay provides a video-like recreation of what the user experienced leading up to an error.

Together, these tools allow you to track errors over time across versions to understand how a recent code change may have impacted user experience.

Performance and Availability Monitoring

With synthetics, RUM, session replay, and mobile application testing, developers can test and monitor the performance of web pages and mobile applications, including:

  • User sessions
  • Views
  • Actions

This enables teams to remediate poor-performing Core Web Vitals before they impact users. 

Behavior Monitoring

Capturing real users’ interactions with their applications, RUM, and session replay gives developers a better understanding of the user experience and identify opportunities to enhance it.

How To Monitor Front End Of Apps: Developing A Front End Monitoring Plan

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Before implementing a frontend monitoring solution, it is crucial to define what to monitor. Start by identifying the specific elements of your frontend that require monitoring and evaluation. This foundational step ensures that you focus on critical aspects directly impacting user experience and align your monitoring efforts with your application’s essential functionalities.

Doing so prevents overwhelming data collection and can direct your attention to the most valuable metrics, enabling a targeted, actionable monitoring approach. Key metrics to monitor include: 

  • Page Load Times: Measure the speed at which your pages load to ensure optimal user experiences.
  • Responsiveness: Assess how swiftly user interactions are processed and displayed.
  • Error Rates: Keep an eye on errors that might disrupt user journeys.
  • User Interactions: Analyze how users engage with your application’s features and functionalities.
  • Conversion Funnel: Track the progression of users through key conversion steps.
  • Third-Party Integrations: Monitor the performance of integrated services or scripts.
  • Device Compatibility: Ensure consistent performance across various devices and screen sizes.

Choose the Right Tool: Find a Frontend Monitoring Solution That Fits Your Code

Once you’ve defined what to monitor, the next step is to choose a frontend monitoring tool compatible with your app’s language. Select a tool that aligns with the programming language and framework used to build your application. Compatibility with your app’s language ensures accurate data collection and meaningful insights.

It allows the tool to effectively interact with your application’s codebase, providing relevant performance metrics and facilitating efficient integration. This compatibility streamlines the monitoring process and enhances the tool’s effectiveness in identifying issues specific to your technology stack.

Monitor System Performance During Peak Activity: Prepare for High Traffic Times

During high user activity periods, closely observe your application’s performance and resource usage. Alerty can monitor your applications for free. Monitoring system usage during peak times provides valuable insights into how your front end handles heavy traffic.

It helps identify potential performance bottlenecks, ensuring your application remains responsive and functional despite intense user demand. This step prevents performance degradation during critical moments and provides a consistently positive user experience, especially during peak usage.

Align Analytics Data with Business Metrics: Connect Frontend Monitoring to Your Bottom Line

Don’t let your hard-earned analytics go to waste. Bridge the gap between data collected from frontend monitoring and the key business metrics driving your organization. Linking analytics data with business metrics provides a holistic understanding of how frontend performance influences your bottom line.

It enables you to quantify the impact of performance on user behavior, conversions, and overall business success. By aligning technical insights with business objectives, you gain actionable insights that drive informed decisions and prioritize optimizations that directly impact your organization’s goals. Metrics that matter: 

  • Bounce Rates: Correlate slow load times with bounce rates to understand how performance affects user engagement.
  • Conversion Rates: Analyze the relationship between frontend improvements and changes in conversion rates.
  • Revenue: Connect frontend performance with revenue fluctuations to assess the financial impact of user experience.
  • User Engagement: Link performance enhancements to user engagement metrics, such as time spent on site and interactions per session.
  • User Journey: To identify critical touchpoints and map frontend performance to different user journey stages.

Monitor, Monitor, and Monitor: The Importance of Consistency in Frontend Monitoring

Regular and continuous monitoring ensures that your application’s performance remains optimal. You can detect issues early by consistently tracking metrics, preventing performance regressions, and quickly addressing emerging challenges.

This step ensures that your front end consistently delivers a user experience that aligns with user expectations and business objectives.

What Are The Challenges Of Frontend Monitoring?

Frontend monitoring has become increasingly complex and crucial. With constant updates, changing technology frameworks, and users from various browsers, devices, and locations, fully monitoring and optimizing the frontend requires multiple tools. All these tools must be part of a unified and seamlessly integrated platform to avoid tool sprawl.

Another challenge is that solutions like RUM may provide a picture of user errors and frustrations but may need to illustrate the root causes. This can be remedied by connecting RUM to application performance monitoring for full-stack visibility and connecting errors directly to their causes. 

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How To Choose The Best Frontend Monitoring Tool?

Person Using Computer - Frontend Monitoring

Start by checking the frontend monitoring tool's compatibility with your website's programming languages and technologies. This is crucial for accurate performance tracking. If the monitoring tool doesn’t support the right languages and frameworks, it might miss important metrics and render your monitoring ineffective.

Cloud vs. On-Premise: Which Frontend Monitoring Tool Is Right for You?

When choosing between cloud-based and on-premise frontend monitoring tools, cloud-based solutions should be your go-to option. These tools are hosted on external servers managed by the provider, offering:

  • Scalability
  • Reduced maintenance overhead
  • Built-in redundancies for enhanced reliability

On-premise tools require installation and self-management, demanding additional resources for:

  • Upkeep
  • Security
  • Upgrades

Ease of Use Matters: Even the Best Frontend Monitoring Tool Won't Work If You Can’t Use It

When evaluating frontend monitoring tools, consider the ease of use, including the intuitiveness of their interface and overall usability. A user-friendly tool simplifies navigation, monitoring parameter setup, and data interpretation, streamlining the monitoring process and shortening the learning curve. This expedites issue identification and resolution.

Agent vs. Agentless Monitoring: What’s the Difference?

When choosing a frontend monitoring tool, you must decide between agent-based and agentless monitoring. Agents are software components integrated into your application’s codebase to collect data and offer in-depth insights.

While they provide more comprehensive monitoring, agents require integration and ongoing maintenance. Agentless monitoring collects data remotely without installing software on your servers. This simplifies setup and ongoing maintenance but may need more comprehensive data.

Security Features: Assessing the Safety of Frontend Monitoring Tools

Not all frontend monitoring tools are created equal. Security features can vary significantly, so assessing them before making a choice is essential. In this context, security involves:

  • Secure data transmission
  • Storage
  • Access control to protect sensitive data collected during monitoring

A breach in monitoring data could compromise user data and expose vulnerabilities.

Security Measures

When evaluating the security of frontend monitoring tools, assess factors like data encryption, access controls, and compliance with relevant data protection regulations to ensure the security of your monitoring tool.

Pricing: Finding the Best Frontend Monitoring Tool for Your Budget

Pricing models for frontend monitoring tools can vary widely. Different tools offer various pricing structures, including subscription plans, tiered pricing based on usage, and pay-as-you-go models.

It’s crucial to ensure that your budget aligns with the chosen plan and understand the features included in each pricing tier. Additionally, evaluate how pricing may scale as your application grows and whether the tool’s features justify the cost. Striking a balance between features, budget, and scalability ensures optimal value from your frontend monitoring tool.

Catch Issues Before They Affect Your Users with Alerty's Free APM Solution

Alerty is a cloud monitoring service for developers and early-stage startups, offering application performance monitoring, database monitoring, and incident management. It supports technologies like:

  • NextJS
  • React
  • Vue
  • Node.js, helping developers identify and fix issues

Alerty monitors databases such as:

  • Supabase
  • PostgreSQL
  • RDS, tracking key metrics like CPU usage and memory consumption

RUM and USM Features

It features quick incident management and Real User Monitoring (RUM) to optimize user experience. Its Universal Service Monitoring covers dependencies like:

  • Stripe API
  • OpenAI
  • Vercel

Alerty uses AI to simplify setup, providing a cost-effective solution compared to competitors. It is designed for ease of use, allowing quick setup, and integrates with tools like Sentry, making it ideal for developers and small teams needing efficient, affordable monitoring.

Catch issues before they affect your users with Alerty's free APM solution today!

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