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Function check of the pseudonymous measuring method

Please note: Only for pseudonymous measurement.

Function of the SZM-Checker

The SZM-Checker provides a log of the measurement pulses arriving in the INFOnline measuring system.

With this log, the customer can track the integration of the measurement into a web page, into an app or into a MEW. Continuous tracking of the functional integration of the measurement from the browser/end device to the measuring system is made possible, thus simplifying testing and troubleshooting tasks.

The SZM-Checker serves to support you and gives you the possibility to verify already in the development and test process whether the integration of the web, MEW or app measurement into your web page, into your MEW or into your app was technically successful.

Alternatively, you can check the integration of the library in apps in the first step in the developer log of the respective development environment (see Integration Guide iOS/Android).

Structure of the SZM-Checker

The SZM-Checker consists of the following components:

SZM-Checker frontend.

  • The SZM-Checker frontend is a website that allows users to request the protocol.
  • The SZM-Checker frontend can be accessed at the following URL:

SZM-Checker app

INFOnline offers for the supported mobile operating systems (iOS, Android)) Apps, through which the logs of an app usage are requested.

The apps are distributed in the following ways:

Operation of SZM-Checker

Note on use

To request a protocol from the measuring system, the following requirements must be met:

  • If the app to be tested transmits only the VendorID and/or InstallationID, this app cannot be tested using SZM-Checker.
  • The log must be requested using the same end device via which the usage process is generated.
  • If web usage is to be logged, it must be requested using the same browser that is subsequently used to generate the web page usage. In the meantime, cookies must not be deleted.
  • If app usage is to be logged, it must be requested using the SZM-Checker app.
  • If MEW usage is to be logged, it must be requested using the same browser that is subsequently used for MEW usage. In the meantime, cookies must not be deleted.

The log is delivered with a time offset of up to 30 minutes after the logging period ends.

Step by step instructions

Unless explicitly described otherwise, the following operating instructions apply to logging a web, an app, as well as a MEW usage process.

Step 1: Step 1: Calling the SZM-Checker.

  • Calling the URL in the stationary browser.
  • Launching the SZM-Checker app. After starting the app, the SZM-Checker frontend will be called automatically.
  • Calling up the URL in the mobile browser.

Step 1a: Confirmation of transmission of various characteristics for device identification (only when using the SZM-Checker app on Android).

Due to changes in the Google Store's terms of use, a query will first appear in the Android app asking whether you agree to transmit additional IDs (checksums IMEI, InstallationID, AndroidID and MAC address) to INFOnline's systems in addition to the AdvertisingID (ADID):

By confirming this query with "Yes," you agree that the SZM-Checker app may send all of the aforementioned IDs to INFOnline for the purpose of identifying your current test device. When you use the SZM-Checker app again on the same Android device, the query will then no longer appear.

If you click "No," you will only agree to the ADID being sent to INFOnline. In this case, you will be asked again for permission to transmit all IDs each time you use the SZM-Checker app on Android.


If you clicked on "No" to allow only the ADID to be transmitted, you will then not be able to use the SZM-Checker app to test Android apps that use a version 1.1.1 or lower of the INFOnline Android Library.

This is because the library uses the ADID for device identification only as of version 1.1.2, whereas earlier versions do not. This means that if only the ADID is transmitted by the SZM-Checker app, the test device cannot be identified in the measuring system and thus no test log can be created when testing Android apps that use a version of the Library lower than 1.1.2.

If you have clicked "No" here by mistake, please restart the SZM-Checker app.

Step 2: Login

Please log in using the access data you received from the INFOnline Customer Service team or from your customer on whose behalf you are developing and testing an app:

If the login is not possible, please contact our Customer Service team directly (see chap. Contact).

Step 3: Confirm terms of use.

After successful login, you will be asked to confirm the SZM-Checker terms of use. This is a prerequisite for its further use.

In case you do not want to confirm the terms of use, please use the logout function at this point and exit the app or browser.


The following points inform you about the check of the measuring impulses. You trigger these by clicking on the "SZM-Checker" button.

Step 4: Entering the logging parameters

After confirming the terms of use, you will be prompted to enter the logging parameters. Please select or complete the following parameters:

  • Site: Please select the site ID assigned by INFOnline that is used by the web page, app or MEW to be logged.
  • Duration: Please select the duration of logging (10/20/30 min). Logging starts at the time you execute the email confirmation (see step 5).
  • Email: Please enter your email address to which the confirmation email and log can be sent. After entering the data, please click on the "Start" button. In the following dialog you will get a confirmation that the order has been saved and a hint for the confirmation e-mail (see step 5):

Step 5: Confirm logging order.

After submitting the logging parameters, you will receive an email to the email address you specified. Please open this email and click on the activation link it contains. The activation link can be accessed from any terminal device.

From the moment of activation, logging of usage in the SZM system begins. The usage processes of your

  • of your stationary browser (Web) / end device (App) / mobile browser (MEW)
  • for the specified site ID
  • for the specified duration


Evaluation of the log

After completion of the logging period as well as the downstream processing time of up to 30 minutes, the log of the usage will be sent to you in CSV format to the specified email address.

The CSV file contains one line per user action/event. Each line contains the following values:

  • time: UNIX timestamp in UTC
  • client: Identifier of the terminal device/browser
  • error: INFOnline error code
  • site: Site ID of the web/app/mew
  • page code: Content code according to Cat 2.0 (Web and MEW: mandatory, App: only for mobile PIs)
  • type: type of retrieved pixel, possible values:
    • cp: content pixel (in normal content pages).
    • fp: Flash pixel
    • xp: test pixel (not counted)
    • oc: content code according to KAT 1.2 (web only; can be empty)
  • sv: control Frabo delivery, possible values:
    • ke or [empty]: frabo is not delivered
    • mo: mobile Frabo will be delivered
    • in: stationary Frabo is delivered
  • mg: SZMnG migration mode specification, possible values:
    • [blank]: SZMnG migration mode is not activated ( at 1st mention explanation 'new generation of scalable central measuring procedures' in brackets).
    • yes: SZMnG migration mode is enabled ( at 1st mention explanation 'new generation of scalable central measuring procedures' in brackets).
  • event: event of the app measurement (app only)
  • parameter: technical parameters of the measurement (automatically determined by measuring system or measuring library), may contain some of the values described here again
  • useragent: user agent string of the browser
  • url: URL called up (Web, Mew)
  • pis: Indication whether measurement pulse is PI-relevant, possible values:
    • 0: measurement pulse is not PI-relevant (only for certain app events).
    • 1: Measurement pulse is PI-relevant
  • dimension: Measurement type (Web, App, Hyb)

Based on this log, you are now given the opportunity to check the user actions you have performed for validity. Please check the respective user actions/events for correct transmission of the above values.

Error codes

The error field gives you an indication of whether the incoming measurement pulses are technically correct. The following table describes the possible codes that are transmitted in the error field. The error codes N are notifications and do not represent an error.

Status-/Error code Meaning
OK No Error (If no error (Ex) occurred, notifications (Nx) are possible)
E2 No parameter specified
E3 Cookie could not be set
E4 Request is neither GET nor POST
E6 problem with ae container
E7 ae container is not JSON
E8 no uuid found
E9 no offerIdentifier set
E10 JSON error
E11 No events inside the ae container


Status/Error code Meaning
N1 No UUID found in ae or mi
N3 uuid found, ie set (app measurement)
N4 no i00 cookie set
N5 cookie renewed due to higher version number
N6 mi found, ie set (hybrid measurement)
N7 ls found, ie set (iPhone)
N8 no id found, use hash
N9 no id found, use hash and JavaScript fingerprint
N10 LSO not accessible
N11 Error in
N13 No page code submitted, default empty code set
N14 Cookie defective, was set again
N15 LSO set, not usable for client resolving
N22 No Privacy Settings specified
N23 Invalid Privacy Setting
Status/Error code Meaning
A1 Referrer not whitelisted (no measurement
A2 Error during client resolving (no measurement)
A3 Session could not be resolved (no measurement)
A4 Checksum in record is not correct (no measurement)
A6 NoScript was used but not activated (no measurement)
A7 Call of an app was filtered due to an IVW correction (no measurement)
A8 Call of a mew within an app (hybrid) was filtered due to an IVW correction (no measurement)
A9 Call of a Mew was filtered due to an IVW correction (no measurement)
A10 Device delivers data from the future via library
A11 JSON in dataset (ae or mi) could not be processed. Defective JSON object
A12 Flash pixel (fp)
A13 Newsletter pixel (np)
A14 Test pixel (no measurement)
A15 Blank code has been replaced by string "Blank_code_unassignable"
A17 Plausibility check (no measurement)
A18 Error plausibility check (no measurement)
A19 Subdomain measurement not equal to subdomain siteconfig (no measurement)
A21 Invalid PI with empty URL (no measurement)

Activation of mobile devices for tests of InApp survey functionality

For the agof InApp survey, a new functionality has been added to the SZM-Checker. This is used to mark development or test devices as testers. This gives app developers the possibility to check the "successful" integration of the InApp survey library in their app. Furthermore, various functional tests regarding the invitation ad and the survey are possible.

Technically, this new feature of SZM-Checker transmits a unique device ID of the testing device to the surveying system. When the app is started, or when the developer triggers an action that could potentially start the survey invitation, the query (based on a device ID) to the surveying system as to whether the test device is in the test survey sample is always answered positively within a certain period of time. Consequently, the device is successfully marked as a test device. The app therefore always starts the invitation ad. The survey data determined in this way does not flow into the agof study.

This function corresponds to the activation of a tester cookie for mobile or for stationary web pages in the SZM(nG) measurement system.


All apps running on a registered tester and linked against the survey library will show the survey if applicable!

Operation of the SZM-Checker

The following describes the process for registering a mobile device for in-app survey testing.

Step 1: Calling up the SZM-Checker.

After starting the SZM-Checker app, the SZM-Checker frontend is automatically called up.

Step 2 a: Confirmation of transmission of various characteristics for device identification (only when using the SZM-Checker app on Android!).

Due to changes in the terms of use in the Google Store, the Android app will first ask you whether you agree to the transfer of additional IDs (checksums IMEI, InstallationID, AndroidID and MAC address) in addition to the AdvertisingID (ADID):

Answering the question is only relevant for the provision of the SZMnG measurement protocol (the main function of the SZM-Checker app). Registering the test device to perform the in-app survey works regardless of which answer you select here. So as far as you only want to activate a test for the InApp survey for your device, you can select any answer here.

Step 2 b: Login

Please log in with the access data you received from the INFOnline Customer Service team or from your customer on whose behalf you are developing and testing an app:

Step 3: Confirm Terms of Use.

After successfully logging in, you will be prompted to confirm the SZM-Checker terms of use. Confirmation of the terms of use is a prerequisite for further use of the SZM-Checker, including the InApp test function contained therein.

To test the InApp survey library, click on the lower of the two buttons.


The test of measurement pulses is initialized by clicking on the upper button. The documentation for this can be found in the INFOnline Manual SZM-Checker.

Step 4: Requesting and initializing the InApp survey test

On this page you will be asked to specify the duration of the InApp survey test:

Within this period, your device is registered on the surveying system as a test device.

After clicking the "Submit" button, the ID of your device is transmitted to the surveying system: The device is then available for InApp survey tests:


Please note that it may take up to five seconds for the above successful submission screen to appear. Please do not press the "Submit" button again during this time.

If you now use your app to be tested within the time specified in the SZM-Checker, you must be shown an AGOF survey invitation ad while using it. By clicking on the "Participate" button, you can start the AGOF survey. The stored site ID that is passed to the survey is now visualized on the display and can be checked for correctness by the tester. The version of the implemented InApp library is also displayed. Please check all click areas and the entry into the survey.

If no survey invitation ad is displayed to you, this indicates a faulty implementation of the survey library.

Interacting with the survey invitation will temporarily block the new survey from being redelivered in the app.

If you want to retest the app, you can either re-mark the device as a tester with the SZM-Checker or wait 1 minute within your selected test duration to retest.

If the test duration you selected has expired and you open the test app again, the test device is locked for 25 hours and can no longer be marked as a tester via the SZM-Checker. In this case, please contact INFOnline Support.

Last update: August 22, 2022