# Anonymous people When people first visit your website or use your app without logging in, they’re anonymous. You know they exist and can see their activity, but you don’t know who they are. You want to identify these people and convert them into members of your audience, users of your service, or customers. ## How it works[](#how-it-works) Most of the things you do in Customer.io revolve around people you know: they log into your service, make purchases, sign up for your newsletters, and so on. And, because you know who they are—you have their email addresses, names, and other information—you can send them messages. But what about people you don’t know? Plenty of people visit your website or open your app without logging in or otherwise providing identifying information. In Customer.io, we typically call these *Anonymous People*. Sometimes we refer to them as *Leads* or *Prospects*: everybody who visits your website or app is someone who *could* potentially become a customer! In Customer.io, you can track and see anonymized activity, like the pages people visit, the actions they take, and so on. But you’re limited in how you communicate with them because you don’t have their email address, phone number, and so on. When you identify these people—by having them sign up for your service, make a purchase, or otherwise provide you with their email address—we’ll associate their anonymous activity with their new profile in Customer.io, and you can use their previously anonymous activity to add them to segments, send targeted messages, and personalize their experiences. ## Some integrations handle anonymous data automatically[](#some-integrations-handle-anonymous-data-automatically) Our JavaScript libraries and some of our mobile SDKs automatically assign people an anonymous ID and track page or screen views. If you use these libraries, you get some anonymous data for free, without doing anything special. Our server-side libraries and APIs don’t automatically track anonymous data. If you want to track anonymous data with these libraries, you’ll need to assign an anonymous ID to people and send events manually. Some of our mobile SDKs don’t support anonymous data yet. We’re adding support in future versions, but you won’t be able to track anonymous screenviews with our Android, React, or Flutter SDKs in the meantime. Platform SDK Supports anonymous data anonymous ID anonymous page/screen tracking Web [JavaScript Client](/integrations/data-in/connections/javascript) ✅ Auto Auto Web [Classic JavaScript (Track API)](/integrations/data-in/connections/javascript/legacy-js/getting-started/) ✅ Auto Auto Mobile [iOS SDK v3 and later](/integrations/sdk/ios/) ✅ Auto Auto Mobile [iOS SDK v2 and earlier](/integrations/sdk/iOS/2.x/) ❌ N/A N/A Mobile [Android SDK v4 and later](/integrations/sdk/android/) ✅ Auto Auto Mobile [Android SDK v3 and earlier](/integrations/sdk/android/3.x/) ❌ N/A N/A Mobile [React Native SDK](/integrations/sdk/react-native/) ❌ ❌ ❌ Mobile [Flutter SDK](/integrations/sdk/flutter/) ❌ N/A N/A Server [Node.js](/integrations/data-in/connections/node/) ✅ Manual Manual Server [Python](/integrations/data-in/connections/python/) ✅ Manual Manual Server [Go](/integrations/data-in/connections/go/) ✅ Manual Manual ## Your goal is to identify anonymous people[](#your-goal-is-to-identify-anonymous-people) You can’t do much with an anonymous person. But if you can identifyThe Customer.io operation that adds or updates a person. When you identify a person, Customer.io either adds a person if they don’t exist in your workspace, or updates them if they do. Before you identify someone (by their email address or an ID), you can track them anonymously. them—if you can learn their name, their email address, and so on—you can send personalized messages, improve their experience in your app, and more. Identifying people is the first step in building a relationship with them. You can identify people when they provide you their email address through a web form, create an account with you, or log in to your service. There are patterns that encourage people to identify themselves (or become customers) on almost every website or app: * offering someone a coupon on their first purchase * encouraging people to sign up for a newsletter * offering a free trial of your service These are all ways to identify new people and start nurturing them to become customers, users, or members of your audience! ## Send in-app messages to anonymous people[](#anonymous-in-app) [Premium This feature is available for Premium plans.](/accounts-and-workspaces/plan-features/) You can send in-app messages to anonymous people who use your website or mobile app if you use our [JavaScript client](/integrations/data-in/connections/javascript/) or [mobile SDKs](/integrations/sdk/). These messages can encourage people to sign up for your service, make a purchase, or otherwise identify themselves. When you create an anonymous message, you’ll set criteria determining where your message appears. People will see your message if: 1. They haven’t been identifiedThe Customer.io operation that adds or updates a person. When you identify a person, Customer.io either adds a person if they don’t exist in your workspace, or updates them if they do. Before you identify someone (by their email address or an ID), you can track them anonymously. 2. They’re on a page or screen that matches your [Page Rules](/journeys/anonymous-in-app#where-does-my-message-appear) [![set page rules determining where your message appears](https://docs.customer.io/images/anonymous-in-app-targeting.png)](#514c8fd17b52cf6a608223ca4048e29e-lightbox) 3. They haven’t already seen your message too many times—determined by the *Frequency* setting in your in-app messages [![set frequency determining how many times a person can see your message](https://docs.customer.io/images/anonymous-in-app-review.png)](#c9723cba367de093e281451ef8ccdd2b-lightbox) ## Anonymous people don’t generate profiles[](#anonymous-people-dont-generate-profiles) Anonymous data in Customer.io isn’t associated with a profile. **Anonymous people don’t cost you anything.** But that’s also because the data they generate is limited and not very useful *until* you identify them. ## What do I do with anonymous data?[](#what-do-i-do-with-anonymous-data) Anonymous data isn’t very useful until you identify a person, but you can still: * Use anonymous page views to trigger in-app messages. These messages aren’t personalized, but they might do things like encourage people to sign up for your service or make a purchase. * Use anonymous responses to in-app messages to figure out conversion rates and other metrics for your anonymous in-app messages. * Send anonymous events to downstream destinations, like your analytics platforms or data warehouses to track traffic and other metrics. Anonymous data really shines after you identify people who were previously anonymous. When you identify people, we’ll [associate their anonymous activity](/journeys/merge-anonymous/) their [profilesAn instance of a person. Generally, a person is synonymous with their profile; there should be a one-to-one relationship between a real person and their profile in Customer.io. You reference a person’s profile attributes in liquid using `customer`—e.g. `{{customer.email}}`.](/merge-people) in Customer.io—their anonymous data stops being anonymous. This lets you respond to the things people did before you identified them. You can use this data to trigger campaigns, add people to segments, and personalize their experiences.