Advertisement monitoring tools focus on providing insight into the advertising activity in your industry. They allow you to examine what your competitors are doing so you can learn from their efforts.
With these tools you can explore the types of ads your competitors are running, where they are running them, how much they are spending and which publishers are effective. You can also analyze the success or failure of competitive ad copy and landing pages.
These tools are related to search engine monitoring but have a very different approach to how the data is used and presented. Although they may provide a small amount of free information or a trial period, they are targeted toward companies who are ready to invest in advertising.
This list is not meant to be exhaustive. If you have suggested additions, please feel free to submit them for consideration.