Great question — answering as the UphillTech team:
Interesting question to ask in a Webmaster forum. First touch and Last touch attribution are attribution methods, which you can use to attribute certain events on your website/app to certain communication messages/marketing channels. MixPanel and Google Analytics, both store user events and allow you pull that event data and attribute to specific messaging that you did to drive the user to do those events. Keep this in mind while I move on to answer the rest of the question. UTM (Urchin Tracking Module) Tags are used internally by Google Analytics (because it was earlier known as Urchin!). Mixpanel does treat them specifically, however, it does so only on a first click attribution model ....
Full answer by Prasad Ajinkya: https://webmasters.stackexchange.com/a/119251 (CC BY-SA 4.0).
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