Colin MacNeill

The Ur-Text Simple Landing Tracking plugin lets you see where visitors to your WordPress pages are coming from.  When visitors land on your site by clicking links with your UTM codes (or navigate through your site internally using UTM-coded links), the request is tracked so you can see how many people are clicking those links.
If you use social media autoposting services like Sendible or Dlvr.it, you can create custom RSS feeds with UTM coded links so you can track all visitors from a specific source.
Also lets you create your own custom non-UTM code for tracking.
Features: 
– Plugin uses no cookies and retains no information about specific visits 
– All stored information is completely anonymous 
– Basic bot and crawler filtering removes bots from your visitor statistics 
– Automatically deletes old data 
– Report showing breakdown of landings 
– Download stats in .csv format

Ur-Text Simple Landing Tracking

Automatically post UTM-coded post URLs to social media using syndicated feeds. Visitor data is fully anonymized and privacy law compliant.

shawfactor

This plugin does tracking/grabbing properly by tracking the data by localstorage only, rather than cookies or session variables. This is a superior way of tracking this data as it does not impact your server or break caching in any way.
It does so by including the Bill Franklins fantastic lightweight JavaScript library for this. I will be including thiis data automatically in my own plugins. But you can access intrsuctions and examples on how access this data in your own opt in forms here:
https://github.com/bilbof/purser

LH UTM Tracking

The proper way to capture UTMs on your (optin) forms.

Ur-Text Simple Landing Tracking vs LH UTM Tracking