Hello @kyczernu Application insights is app-level telemetry geared towards monitoring and troubleshooting applications and as a result, it collects data specifically for the configured apps. As a result, it offers detailed insights into application performance, exception, dependencies, visualizations with some cool features like application maps, transaction tracing and end-to-end monitoring. And, all these insights are powered by the telemetry data which can be stored in Log Analytics workspace. However, because it's a very specific solution with a focus on application, it suffers from the fact that it's just focused on the specific application level telemetry and cannot provide anything beyond this.
The Logs Ingestion API, on the other hand, is more of a general purpose log data collection and storage method. It can collect different log data from different sources, not just apps. As a result, this is a more broad-based solution that can act as a centralized log storage across various services with the ability for query for information using KQL queries. Hence, you will find that you can create custom reports that span across services and gives you a complete holistic picture of your environment and not just your app.
In a nutshell, if your focus is just on applications, then, Application Insights might be the solution that you're looking for. However, if you want a more generic solution that'll help you get a complete picture of your entire environment, Log Ingestion API (or Log Analytics workspace, in general) might be your friend.
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