Introduction
OneLink™ is a unique AppsFlyer tracking link which advertisers can use to utilize 3 primary features with a single click:
- Device Detection And Redirection: OneLink is able to detect the device type (Android, iOS, desktop etc.) when clicked and redirect the user to a matching destination.
- Deep Linking: If the advertised mobile app is already installed, OneLink is able to support launching the app after click and/or serving the user with personalized content (such as sending a user to a specific activity/page in the app).
- Deferred Deep Linking: If the advertised mobile app is not installed, OneLink is able to support serving a user with personalized content (such as sending a user to a specific activity/page in the app) on the first launch of the app after install.
Advertisers usually deploy OneLink with their owned media, such as email and SMS campaigns, website banners and landing pages, viral posts on social media or even QR codes on physical posters. Nevertheless, it's also possible to use OneLink with integrated partners.
This guide covers OneLink basic setup, which enables device detection and redirection.
Once this basic setup is complete you can continue to the step-by-step Deep Linking Guide.
Example
AwesomeCom has released a new app for Android and iOS. Jill, the mobile marketer, decides to launch an SMS campaign using AwesomeCom's users mobile phone numbers database. The short message contains a call to action and a single OneLink URL.
All Android users clicking the link are redirected to the app's page on Google Play. All iOS users clicking the same link are redirected to the app's page on iTunes.
The campaign manages to convert 23.5% of AwesomeCom's registered users to mobile users using OneLink!
Device Detection And Redirection Flow
When you are using an engaged device and click on OneLink the following steps occur:
- You are redirected to AppsFlyer's servers
- There, your click URL and its parameters are saved for later, for attribution and deep linking purposes, should you choose to install the app
- Immediately afterwards, based on the user agent of the device, the device type is detected
- You are then redirected to the designated destination according to OneLink's template (see below), which fits your device type
There are two stages required for OneLink's setup to achieve these steps:
Note
OneLink also supports the following platforms:
- Android - Android based Smart TVs
- Apple - Apple TV (tvOS)
- Amazon Fire TV - for Amazon Fire TV use the Custom Android APK URL option
- Windows - All Universal Windows Platforms including Xbox
OneLink Template Configuration
The OneLink template is where all the different destinations per device types are defined.
Once the basic OneLink setup is complete, you can create many custom links with different parameters, that lead to the same destinations stated in the OneLink template (except if overridden).
Each mobile app under an AppsFlyer account can be defined in multiple OneLink templates. For details on assigning an app to more than one OneLink template go here.
Important!
Although it is possible to define a mobile app in multiple OneLink templates, in most cases there is no need for it. Generally, an app should only be set up ONCE in the OneLink template.
Use this setup to create many custom tracking links that have different attributes, but lead to the same destinations.
OneLink List Page
The OneLinks list window is at account level, meaning it is common between all apps and contains all the OneLink templates of the account.
1. From the dashboard of any of your apps, under the Configuration section, click Configure OneLink to open the OneLinks list window
Each generated OneLink has its own unique OneLink ID (provided the OneLink sub domain is defined): http://myapp.onelink.me/onelinkid.
Each OneLink also has its own custom name.
2. For a new OneLink template click 
.
3. To work on an existing OneLink template click the respective OneLink name.
Note
It is not possible to delete OneLink templates once they are set. This is because any existing tracking links based on deleted OneLink templates stop working and may redirect users to a 404 page (page not found).
Instead, you can simply edit existing OneLink templates.
After selecting an existing OneLink template, or adding a new one, the OneLink configuration page opens.
OneLink Configuration Page
From here you can set the destinations for iOS, Android and Windows phone devices. In addition, there are some more advanced destinations you can set. The following explains each of these options.
OneLink Template Name
Set the OneLink name here, preferably for the participating apps in the template. This is optional, but if you don't set the name, the default name "Untitled OneLink" is generated for the template.
You can change the OneLink name at any time.
iOS Apps
Using the dropdown menu, select the iOS app you want the user to be redirected to in the App Store.
Advanced Options
- Custom Landing Page
To redirect iOS users to a destination different from the App Store, populate a destination URL in the Custom iOS Landing Page URL field.
To set the remaining advanced OneLink options for iOS toggle the Enable Universal Links for deep linking button to On.
- App ID Prefix
Application-identifier key in your app's entitlements - iOS Test Apps
If you are using a test app to develop your iOS app, you can test it using OneLink.
Complete the App ID prefix (same as 2) and the iOS App Bundle ID, as defined on XCode.
Note
Both values are found on developers.apple.com in the Identifiers >> App IDs section. Just click the corresponding registered App ID as shown below.
- iPad
If your iOS app has a different iPad version, you can redirect iPad users to it. Use the iPad dropdown menu to select a different iOS app from your account, that the iPad user is redirected to in the App Store.
Android Apps
Using the dropdown menu, select the Android app that you want the user to be redirected to in Google Play.
Custom Android APK URL
- Insert here the link for your Android app, if it is out of Google Play, Android users are redirected to this link.
- Enable App Links for deep linking
"App Links" is an advanced method for performing deep linking on Android devices from Android OS version 6.0 and above. For more details go here.
Windows Phone App
Select the Windows Phone app that you want the user to be redirected to in the Windows Phone store, and add its URL in the Custom Windows Phone URL box. 
Additional Configuration
Note
The Deep Linking (iOS9/Android 6 and above) sub-domain field must not contain a '.' For example, MyApp is valid but com.MyApp is not valid.
Kindle Fire: Populate an Amazon Store ASIN or an alternative URL for Kindle Fire users
Website URL: Populate any destination URL for desktop users.
Note
The first two additional configuration parameters are covered in the Deep Linking Guide.
Creating Custom Links from the OneLink Template
Now your OneLink template is ready, you can create parameter-rich tracking links using it. These tracking links can differ by values such as the media source and campaign names (e.g. emails, website, banners etc.), but the basic OneLink redirections are common for all links (except if you override them).
You can create OneLink tracking links manually using the custom tracking links setup window. For details click here.
Alternately, if you want to automatically create OneLink tracking links or by bulk, you can do this using the OneLink REST API.
Testing OneLink's Redirections
To test your newly-configured OneLink template follow these instructions:
1. Create a Multi-platform 'test' custom tracking link
2. Select the OneLink configuration the tracking link is intended for
3. Fill in the media source and campaign names. You can create different links for any type of tests you run. However, AppsFlyer recommends using the test media source name for all of them
Tip
Always prefer using test media source (&pid=test) when you test anything with AppsFlyer, to see all test results under the test media source. Add the test type under the campaign name parameter (&c={test type}, e.g. &c=redirections) to distinguish between different test types with the campaign name parameter.
4. Generate the tracking link and use either the long or short URL for testing
Example:
https://go.onelink.me/{AUTO_GENERATED}?pid=test&c=redirections
5. For every OS version configured in the OneLink configuration page:
- Send the test URL - To the respective whitelisted device using email, QR code etc.
- Click on the test URL - Verify the device is redirected to the configured destination (Google Play, iTunes, web page etc.)
- Install the mobile app - On the device and launch it
- Check results - On the dashboard's overview page look for a new click and install under 'test' media source and the campaign name you put in the URL (e.g. redirections)
Warning
Completing the above tests successfully means your app is ready for performing OneLink redirections only. For deep linking tests click here.
Overriding OneLink's Template Destinations
Although OneLink's template-configured redirections are common for all tracking links that use it, you can override them with custom parameters. Placing the following destination parameters on the tracking link sends clicking users to the values stated in the link instead of the template's configured values.
Destination Parameters
| Destination Parameter Name | Description | AppsFlyer's Tip |
|---|---|---|
| af_ios_url | Redirect iOS users to a different URL than the app's page on iTunes | Use this for landing page redirections, or as fallback in case deep linking fails |
| af_android_url | Redirect Android users to a different URL than the app's page on Google Play | Use this for landing page redirections, or as fallback in case deep linking fails |
| af_r | Redirect users to the specified URL on all operating systems and platforms | Use this for landing page redirections |
| af_web_dp | Redirect desktop users to a different web page than configured in the OneLink template | Use this to keep attribution data of desktop users on other platforms (e.g. Google Analytics or Omniture) |
| af_dp | The path for an internal activity in the app that users are deep linked into | Use this for deep linking and retargeting |
| af_ios_fallback | Supply fallback URL for users of iOS 10.3 and above | Use this to improve the broken flow for iOS 10.3 users |
Warning
Do not use any of the following characters as part of the destination parameter values (not even URL-encoded). Using them blocks OneLink's redirection or deep linking actions.
The characters are: []<>;(){}'`"
Example
Android users that click the following example link are redirected to google.com rather than the preconfigured android app page on Google Play. Clicking iOS users are redirected to apple.com:
https://go.onelink.me/{AUTO_GENERATED}pid=test&c=redirections&
af_android_url=http%3A%2F%2Fwww.google.com&
af_ios_url=http%3A%2F%2Fwww.apple.com
OneLink & Social Apps
Advertisers may want to use OneLink with "viral" posts on social apps, as potential users that are exposed to such posts cannot be targeted in advance according to their devices.
Unfortunately, limitations set mainly by Apple's Universal Links, in conjunction with restrictions of some of the social apps, complicate the use of OneLink for deep linking, or even sometimes for basic device recognition, redirection and attribution.
The following table summarizes what you can do with OneLink in today’s popular social apps:
| Social App | Android Redirection | Android Deep Linking | iOS Redirection | iOS Deep Linking |
|---|---|---|---|---|
| Y | Y | Y | Y | |
| Facebook Messenger | Y | Y | Y | Y |
| Y | N | Y | N | |
| Line | Y | Y | Y | N |
| N | N | N | N | |
| Slack | Y | Y | Y | Y |
| Y | Y | Y | Y | |
| Y (See WeChat FAQ) |
N | N | N | |
| Y | Y | Y | Y |
The Workaround for Social Apps
To avoid the aforementioned OneLink limitations, and still enable device redirection on social apps' posts, we recommend using landing pages.
The user's flow is as follows:
1. User clicks on the landing page link inside the post on the social app
2. User is redirected to a landing page
3. Landing page contains a "Download app" button, with OneLink behind it. User clicks the button
4. The regular OneLink flow follows including deep linking and attribution using fingerprinting
Note
The conversion rates for landing pages may be a bit lower than the original sources, due to the second click required from the users.
For performing deep linking from social media posts with OneLink go to the deep linking guide.
Using OneLink with Integrated Networks
OneLink is mainly used with owned media, and not with ad networks.
It is rare for ad networks to require OneLink since they usually advertise on apps. This enables them to know the user's platform, device ID etc., so their app and platform-specific tracking links suffice.
However, sometimes ad networks don't know their users' platform in advance, for example when they run email or SMS campaigns themselves.
OneLink Setup with Integrated Networks
- Go to Integrated Partners on your Android app's dashboard and select the relevant ad network.
- Copy the app's tracking link from the setup window and save it to an external document.
- For your iOS app, repeat steps 1+2.
Now build the tracking link:
- Make sure OneLink is properly set up
- Create a basic OneLink URL in the Custom Tracking Link window and save it to an external document. For example: https://greatapp.onelink.me/3287867539?
- Add the exact PID of the integrated partner to the link https://greatapp.onelink.me/3287867539?pid=network_int&
- Add ALL parameters from BOTH tracking links
If the tracking link of the iOS and Android app are identical, simply copy the parameters from either one of the links. Otherwise make sure you have all the parameters from both links.
If all the integrated network parameters are added correctly, once OneLink is clicked and redirected to the right platform, the required parameters are sent to the network within a postback after the user installs.
Example
https://greatapp.onelink.me/3287867539?pid=network_int&c=email&
idfa{$IDFA}&gaid={$GAID}&clickid=$SITEID&
af_sub1=[pixel_code]&af_sub2=[creative]
The network uses either the IDFA or GAID parameters according to the client's device platform and disregards the other parameter.
FAQs
Yes, using target="_blank" in the HTML href tag does not result in redirecting to Google Play.
Yes, there are several Instagram limitations:
- Due to the way Instagram renders the text of a page post, links do not become clickable when entered into a post caption.
- Instagram profile descriptions do not support clickable links.
- Linking from profile website links is possible, however it directs to the App Store all the time since Universal Links are not supported in Instagram (iOS only).
To overcome this, OneLink can recognize clicks in WeChat and loads a dedicated landing page instructing the user to click the options button and then to click Open in Browser. This opens the redirect URL defined in the OneLink configuration.
If the user’s WeChat language is registered as Chinese, OneLink generates a localized version of the landing page:
