View-through attribution guide

At a glance: AppsFlyer supports impression recording and view-through attribution via a large number of ad networks.ImpressionAndVTAttribution.png


View-through attribution



  • Impressions: Record mobile users who view ads for a minimum amount of time, regardless of any following clicks or installs.
  • View-through attribution: Ad impressions that result in user action (install), without the user clicking on an ad.

Ad networks send ad impression data to AppsFlyer in either aggregated format or via API, similar to clicks API, containing user-level data.

Impressions reported with user-level data can be attributed as view-through installs. These impressions are available in raw data reports after they are attributed to a user action like install or retargeting engagement.

Viewing the impressions data

Overview dashboard headline metrics


  • Impressions data is available in the Overview dashboard and other reporting options in the platform.
  • The impressions metric relates to the number of impressions displayed during the period specified. 

Impressions in the aggregated performance report

The table shows the impressions count per each media source, campaign, country etc. for the selected date range. For networks not supporting impressions recording (e.g. Google AdWords), the "N/A" value is displayed in this column.

Impressions versus clicks

Are all clicks also counted as impressions (where impressions data is available)?

Generally, the answer is yes. After all, for any user to click on an ad, the user must see it first.

However, in some cases there may be a click without a preceding impression. Ad networks define impressions by a minimum exposure time to ads, e.g., Facebook sends an impression when users watch an ad for at least one second. In cases where a user is exposed to an ad for less than the minimum time for impression recording, but clicks the ad very quickly, there is a newly counted click but not a new impression.

Read more about the definitions of impressions and clicks by major integrated partners. 

Building impression links

When a user performs an ad impression the ad network can fill in the user specifics in a URL and send it to AppsFlyer in real time. This attributes an impression to the network in real-time, and also an install, if it follows.

The URL can contain any valid parameter from AppsFlyer attribution links, but it has some specific requirements:

  1. The base URL is Both HTTP and HTTPS protocols are supported
  2. Use a GET request
  3. Device ID, either IDFA ("idfa=") or GAID ("advertising_id="), on the impression link is mandatory
  4. If GAID isn't available for some reason include Android ID ("android_id=") on the link. If that isn't available use IMEI ("imei=)
  5. The Device ID values can be hashed for better security using SHA1. The parameter name should begin with "sha1_" and be followed by the parameter name and the hashed value, i.e. sha1_idfa, sha1_advertising_id, sha1_android_id and sha1_imei
 Example{app-id}?c={campaign name}&pid={media source}
&af_viewthrough_lookback=1d&af_prt={agency_name}&af_siteid={site id value}
&af_sub1={free value}&idfa={idfa value}
It is very important to send the impression data as early as possible to AppsFlyer so that the data can be attributed correctly.

Ad networks that want to support view-through should contact their dedicated Partner Development Manager or contact

Custom impression links

Advertisers can also utilize attribution impression links, with their own custom media, e.g. website banners.

When advertisers create custom attribution links, they get full impression links, which can be fired every time their users engage with their owned ads. By doing so, advertisers can measure the impressions to clicks conversion rates of their owned media, and find the most engaging spots to use.

Custom impression links can also be used to perform view-through attribution of mobile website visitors. 

Learn more about creating custom impression URLs.

View-through attribution overview

View-through attribution allows you to measure installs coming from ad impressions, where the user has not clicked on the ad. Therefore, all view-through installs are also first counted as impressions.

When a new install occurs, if there is no relevant click, AppsFlyer looks for a possible matching impression. If a match is found then view-through attribution takes place.

However, if both clicks and impressions exist within the attribution lookback window, the last click always prevails and gets the attribution. The impressions preceding the last click, are then recorded as assisting the attribution.

View-through attribution supports: 

Viewing the view-through data

The count of view-through installs is presented in the dashboard's overview page, as part of the Aggregated Performance Report table.

The view-through installs count should always be lower than the number of impressions, as it is a contained group within the impressions group.

However, there may be sources with view-through installs although the impressions data is not available (N/A). This only happens for SRNs, that don't have impression data collection enabled or supported, that do reply with the correct attribution touch type, click or view.

Raw data view-through installs

In the raw data installs and in-app events reports, when under the attributed_touch_type column you see the impression value, it is a view-through attributed install.

Some ad networks in some conversion scenarios restrict user-level data sharing. In this case, user-level data are attributed to the restricted media source.

View-through attribution lookback window

You can set the view-through lookback window per each ad network, that supports view-through attribution, on its partner configuration page.

The view-through lookback window is the maximum amount of time, that can pass from an ad impression and until the first app launch, in which the user gets attributed to the ad serving network.

The recommended and the default view-through attribution lookback window is 24 hours. The possible view-through lookback windows are 1 to 48 hours (1h – 48h) or 1 to 7 days (1d – 7d).

For Ad Networks using impression attribution links:

  • A specific parameter appears on the attribution link – af_viewthrough_lookback
  • If the af_viewthrough_lookback parameter does not appear in the attribution link, the default lookback window is 24h.

Enabling view-through attribution

View-through attribution is enabled by default. If AppsFlyer receives a valid impression attribution link (with IDFA/GAID), this impression participates in the attribution flow unless the view-through attribution is disabled in the partner setup page.


Since view-through attribution is enabled by default, it is important that advertisers contractually agree with the network in advance whether or not their view-through attribution should be enabled.

Disabling view-through attribution

It's possible to disable view-through attribution per media source. If impressions are received and the view-through attribution is disabled, the user can still see the impressions in the dashboard, but the attribution process ignores these impressions.

To disable view-through attribution:

  1. Open the relevant media source configuration
  2. Clear select the view-through attribution option.
  3. Click Save & Close


With SRNs, disabling view-through attribution on AppsFlyer doesn't do the same on the networks side. Keep the view-through setup on AppsFlyer and the networks aligned to avoid discrepancies.

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