AppSignal is a subscription-based application performance monitoring (APM) tool designed for developers and IT professionals. It offers a unified interface for error tracking, performance monitoring, and custom metrics, making it ideal for those building enterprise-grade Node.js applications. Users can monitor server metrics including CPU, disk, and network usage, while setting up real-time alerts for anomalies to prevent unexpected downtimes.

With support for multiple programming languages and frameworks, including Ruby on Rails and Elixir, AppSignal enables users to collect and visualize metrics through customizable dashboards. The platform caters to a wide range of organizations, from small businesses to enterprises, and integrates with various services like Slack and Zenduty. A free trial is available, and pricing begins at $19 per month.