> ## Documentation Index
> Fetch the complete documentation index at: https://formbricks.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Understanding Formbricks Survey Types

> This guide explains the differences between Formbricks Link Surveys and Website & App Surveys to help you choose the right option.

## Quick comparison

| Feature                       | Link Surveys                                           | Website & App Surveys                                                   |
| ----------------------------- | ------------------------------------------------------ | ----------------------------------------------------------------------- |
| **Best for**                  | Known touchpoints                                      | Behavior-based intercepts                                               |
| **SDK required**              | No                                                     | Yes                                                                     |
| **Delivery**                  | Email, SMS, push, or webview                           | Triggered in-app by SDK                                                 |
| **Segmentation**              | You control externally                                 | Built-in via Formbricks                                                 |
| **Survey fatigue prevention** | You control externally                                 | Automatic                                                               |
| **User identification**       | [Personal Links](/surveys/link-surveys/personal-links) | [SDK user attributes](/surveys/website-app-surveys/user-identification) |

## Link Surveys

Also known as **invitation-based surveys**. No SDK needed. You control when and who receives the survey, often through CRMs, marketing tools, or similar platforms.

<img src="https://mintcdn.com/formbricks/HVXK9qhSV5tjWeAg/images/surveys/best-practices/link-surveys-vs-in-app-surveys/link-surveys-example.webp?fit=max&auto=format&n=HVXK9qhSV5tjWeAg&q=85&s=2deeeac8175aad1da6237e2287b5bbd3" alt="Link survey example" width="2606" height="1486" data-path="images/surveys/best-practices/link-surveys-vs-in-app-surveys/link-surveys-example.webp" />

### Delivery channels

* Email
* SMS
* Push notification
* In-app webview

### URL features

* **[Hidden Fields](/surveys/general-features/hidden-fields)**: Pass user ID, order ID, or any identifier
* **[Data prefilling](/surveys/link-surveys/data-prefilling)**: Pre-populate answers and optionally skip prefilled questions
* **[Personal Links](/surveys/link-surveys/personal-links)**: Generate unique survey links for individual contacts

### Webview with Embed mode

For mobile apps, you can display Link Surveys in a webview with full control over when the survey appears. Your app decides the timing—open the webview when the moment is right.

**Enable Embed mode** by appending `?embed=true` to the survey URL:

```
https://app.formbricks.com/s/<surveyId>?embed=true&userId=123
```

**Listen for events** to close the webview automatically:

```javascript theme={null}
window.addEventListener("message", (event) => {
  if (event.data === "formbricksSurveyCompleted") {
    closeWebView();
  }
});
```

This approach gives you full control:

* **When**: Your app opens the webview at the right moment (after purchase, case closed, etc.)
* **Who**: Personal links allow you to have unique links for identified contacts.
* **Display**: Survey renders inside your app
* **Dismissal**: Close the webview on completion or user exit

Learn more in the [Embed Surveys guide](/surveys/link-surveys/embed-surveys).

### When to use

* You already decide externally who should receive which survey
* Survey timing is tied to a known event such as a click on a link or button and in **each case**, you want to show the survey
* You want fastest approach to production
* Your platform doesn't have a supported SDK
* You don't need Formbricks attribute-based targeting & survey fatigue controls

## Website & App Surveys (SDK)

Also known as **intercept surveys**. Requires SDK integration. Formbricks handles targeting, triggering, and survey fatigue.

<img src="https://mintcdn.com/formbricks/HVXK9qhSV5tjWeAg/images/surveys/best-practices/link-surveys-vs-in-app-surveys/in-app-surveys.webp?fit=max&auto=format&n=HVXK9qhSV5tjWeAg&q=85&s=b8642d6dbe3af7a9bf1d201d399affe9" alt="In-app survey example" width="928" height="534" data-path="images/surveys/best-practices/link-surveys-vs-in-app-surveys/in-app-surveys.webp" />

### In-app features

**[Action tracking](/surveys/website-app-surveys/actions)**

Track in-app events and trigger surveys based on them:

```javascript theme={null}
formbricks.track("action_name");
```

**Built-in survey cooldown**

* Global waiting time (e.g., show max 1 survey every 7 days per user)
* Per-survey overrides for high-priority surveys

**[Segment-based targeting](/surveys/website-app-surveys/advanced-targeting)**

Target surveys based on user attributes (plan type, language, feature flags).

**In-app display**

Surveys appear inside your app as modals or slide-ins.

### When to use

* You want Formbricks to handle who sees which survey
* Surveys should trigger based on user behavior (page views, clicks, custom events)
* You want automatic survey fatigue prevention
* You need percentage-based sampling (e.g., show to 10% of users)

## Decision guide

<AccordionGroup>
  <Accordion title="Do you control survey triggering externally?">
    Use **Link-based Surveys**. Send the URL when the moment is right, even for in-app surveys.Pass context via Hidden Fields.
  </Accordion>

  <Accordion title="Should surveys trigger based on in-app behavior?">
    Use **Website & App Surveys**. The SDK tracks actions and triggers surveys automatically.
  </Accordion>

  <Accordion title="Do you want automatic survey fatigue prevention?">
    Use **Website & App Surveys**. Built-in cooldown prevents over-surveying.
  </Accordion>

  <Accordion title="Need the fastest path to production?">
    Start with **Link Surveys**. No SDK integration needed. Add SDK later if you need behavior-based triggers.
  </Accordion>
</AccordionGroup>

***

**Need help?** [Join us in GitHub Discussions](https://github.com/formbricks/formbricks/discussions)