posted this on February 11, 2013, 6:58 PM
There are many differences between Angelfish Software and Urchin - this article addresses the basics. If you have additional questions, please ask us.
1) Angelfish is a completely separate product.
Angelfish doesn't share any code with Urchin, but the end result is the same: Angelfish processes your website data and creates detailed usage reports.
2) Processing Speed Differences
Angelfish doesn't process data as quickly as Urchin, but there's a very good reason!
With Angelfish, we chose report flexibility over processing speed. This means Angelfish provides features that Urchin doesn't have, like segmentation by content, nested segments, and any combination of dimensions and metrics via the API.
Urchin processes data quickly, but Angelfish provides many more details in the reports.
3) No Row Limits, a.k.a The "other" Problem
Have you ever seen the “other” row in Urchin after the monthly unique row limit is reached? You won’t see it in Angelfish. When working with large datasets, Angelfish shows you everything.
4) The numbers will be close (but not exact).
When you compare web analytics data between two different products, you'll see different numbers in each product. There are a variety of reasons for this, like differences in tracking method or filtering logic. Differences are typically less than 20% but can be significantly higher in some cases.
For example...Angelfish will show you all traffic unless you specifically exclude it, whereas Urchin automatically strips out traffic that doesn't match a "user agent whitelist". This whitelist is intended to exclude robots and spiders, but also excludes traffic from new mobile devices. Using this scenario, a mobile-heavy website will see a significant difference in data between Urchin and Angelfish.
5) You can migrate your Urchin data to Angelfish
There are two ways to accomplish this:
If you have historical logs that contain __utm.gif requests, you can process them directly in Angelfish with the UGA tracking method: