Nope, we dont have any mobile apps. The common social media apps are passing the values in evar as well.
Tried breaking down with different dimensions, the only abnormality i observed is that Andriod Operating System (Andriod 11 to Andriod 14) has the highest unspecified values.
Are there any limitation on Andriod for AA?
Not typically.. I checked, and I can only find a very small number of page views that got an unspecified in my campaign data... and it's only against a handful of specific URLs.. I suspect something else loaded on the page that caused a cascading failure on the script used to process the page...
However, if you are seeing an issue that seems to be related to Android, you may need to do some extra testing on android... You may need to use a proxy tester like Charles, Fiddler, or HTTP Toolkit to send the internet from an android device through your computer so you can see what is being captured... or use a service like BrowserStack and watch the logs while testing using an android device there (this requires a BrowserStack account.. you may need to check with your Dev or QA team to see if they have an account you can use; or if they can help run the test).