Best one I've used so far, but the interface becomes messy if I want to add a lot. Please, dev, find a way to add the entries I want, and to check the box if I want them to show, and when I want to. And a way to add easily common new user agent without searching for hours on the internet, and fix the icon, I don't know if it's possible to make it multi-process.

I've used it with the entries found on: www.techblog.willshouse.com/2012/01/03/most-common-user-agents and tested here: www.whatismybrowser.com and here: www.whoishostingthis.com/tools/user-agent