I am looking for a Crash Reporting tool to use with my project and would like to know more about the solutions that Unity offers.
Both services provide real-time crash and exception reporting from Unity Projects. While Unity Cloud Diagnostics is a free product with which the parameters depend on your Unity License, Unity Cloud Diagnostics Advanced is a paid product with more advanced features and benefits.
For Unity Cloud Diagnostics, the following chart breaks down the benefits depending on your Unity Editor License:
With Unity Cloud Diagnostics Advanced (powered by Backtrace), you get more capacity (more total errors and size of reports), more customization (the ability to customize individual reports as well as aspects the service offering), and the ability to use the tool with other game engines and a wider variety of integrations. See the chart below for a high level comparison to Unity Cloud Diagnostics.