How to Choose the Best Google Ad Manager Monitoring Tool in 2026: A Publisher's Buyer Guide

"What's the best monitoring tool for Google Ad Manager?" It's the most common question publisher ad ops directors ask once they've decided manual GAM checks no longer scale. The answer depends on seven specific evaluation criteria - and most publisher teams get at least two of them wrong on their first purchase. This buyer's guide breaks down what to look for, what to avoid, and how to make a decision your team will still be happy with 12 months in.