Custom Events and Tags: How and When to Use Them for More Powerful Segmentation

Give your app’s marketing a personal touch with custom event data and tagging through Mailchimp’s API.

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Your app is getting more and more users every day. This is a good thing! But in order to keep improving upon your ambitious goals and sophisticated marketing strategy, you need to make the most of your data. Which is why we’re thrilled to let you know that we have just the dynamic duo to help: custom events and tags.

When you use a Marketing CRM, Mailchimp’s or otherwise, you can easily access all of your data in one place. Tags and events are CRM tools that help present a more robust picture of your audience. But they’re also unique tools that complement each other nicely. For instance, did you know you can pull in custom data from your app to get a better sense of who your users are and all the ways they're engaging with your brand?

With the help of an in-house developer (or a hired expert), you can use our API to pull data for custom events or by automatically tagging contacts based on data from another app. And bringing this information into Mailchimp can create some effective results. Just take it from one of our customers, UrbanSitter.

“We use the Mailchimp API to pull in critical customer data so that we're able to segment based on things like whether a parent has booked yet, when was the last time they booked, if a sitter has completed their profile, and where a parent lives.”

UrbanSitter co-founder and VP of Marketing, Daisy Downs

Understanding the difference between custom events and tags

Before you start digging in, it’s important to understand what custom events and tags are, how they differ from each other, and how you can best put them to work.


Custom events let you capture the in-app activity of your contacts, which lets you unlock the power of behavioral targeting. When you leverage events, you can create personalization at scale based on what your customers are doing—or not doing—at specific dates and times. It’s the best way to turn the activity data from your app into marketing actions quickly, in ways that are most meaningful to your audience. And best of all? Mailchimp API gives you endless customization options.

Here are some examples of custom events you might consider tracking:

  • Downloaded an application
  • Installed an application
  • Completed registration or signup
  • Started free trial
  • Completed first in-app action
  • Started paid subscription
  • Upgraded to next subscription tier

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Whereas events let you know if something happened or didn’t happen, tags are attributes of people in your audience. For example: a customer might be a “premium user” (tag), and you can track their behavior when they “upgrade to premium” (event). Mailchimp customer Roadie, for example, uses tagging through Mailchimp’s API to create and send personalized, automated messages to the people and businesses that use their services.

“Rather than manually uploading or inputting audience data, we're using the Mailchimp API to bring in user information that we can act on,” says Content Manager Jamie Gottlieb. “The Mailchimp API has been crucial in being able for us to scale that as a company.”

Tags can tell you who your audience is and unlock a more granular view of it. Here are some useful examples of tags:

  • Membership level
  • Job title
  • Type of user
  • Sign-up source
  • Type of service

Perhaps best of all, events and tags can work together to paint a more complete picture of who your contacts are and how you should market to them.

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How to set yourself up for success

Now that you understand the difference between custom events and tags, let’s look at how to incorporate them into your marketing strategy. If you strategize beforehand and work closely with a developer, you’ll be able to make the most of your data.

Step 1: Identify your most actionable data elements
Before you start putting these tools to work, think about what information you want to capture and how you’ll use it in your marketing. For example, knowing how your customers joined your audience is a critical piece of data that can help you market smarter. With tags automatically applied to your landing pages, you can track sign-up sources for future use in your personalized marketing.

We also provide automatic tags through a number of integrations:

As you build out your strategy, put together a wish list of important actions your users take that would be helpful for your marketing.

Step 2: Work with a developer to automate tag and event data collection
Mailchimp’s powerful API lets you customize your events and tags. Once you know what you track, you need to get your integration built so can start tracking in Mailchimp. This is a great way to take your personalized marketing to the next level. Talk to a developer about the possibilities based on the wish list you put together while strategizing. Don’t have a developer? Our experts directory can help.

Step 3: Launch personalized marketing that grows with your business
Now that you’re pulling in loads of data, you need to figure out how to best put it to use. Tags and events can both deliver triggered messages on behalf of your organization, which saves you time and increases the ROI of your marketing.

Once you start tagging contacts, you’ll see your most commonly used tags on your audience dashboard, so you can start sending targeted campaigns to these segments with just a few clicks. You can even trigger automations based on tags to instantly follow up with a targeted message as soon as a tag is applied.

You can also segment based on events and tagging data, sending targeted messages based on what you learn. And once you get the hang of it, try saving time by automating follow-up messaging based on significant tags or events that often occur.

Unlocking the possibilities

At the end of the day, more data means more personalized marketing and better targeting. Your audience data is the most valuable tool you have for improving your marketing and growing your business. Get started with tags and custom events today to unlock the possibilities.

Talk to your developer about pulling custom event data from your app into Mailchimp.

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