Conversion tracking is critical for Google App campaigns because it allows you to measure the effectiveness of your ads and determine whether they are meeting your business objectives. Without conversion tracking, you would not be able to accurately measure the number of people who take a specific action on your app or website after clicking on your ad.

By setting up conversion tracking, you can see how many people are installing your app, making in-app purchases, or completing other actions that are important to your business. This information can help you optimize your campaign and improve its performance.

For example, if you find that a particular ad is not generating many conversions, you can use this information to make changes to the ad or targeting to try and improve its performance. On the other hand, if you see that an ad is performing well, you can allocate more of your budget to it and try to replicate its success.

Overall, conversion tracking is an essential tool for understanding the effectiveness of your Google App campaigns and making informed decisions about how to optimize and improve them.