I just signed up on Agestudy.nl and installed the App, what should I do next?

You will receive an email from Leiden University (email address: agestudy@fsw.leidenuniv.nl) within the coming days with further instructions, including your participation ID which needs to be pasted into the App.

Where can I download the App? Is it free?

Logo quantactions

After installation, my App says it is ‘Initialising’ is this normal?

Yes, this is normal and may remain like this for the next few hours. If it persists for more than a day then please email us at agestudy@fsw.leidenuniv.nl

How do I activate the TapCounter App to the study?

Step 1. Log in and go to the account tab


Step 2. Open the TapCounter App and press the menu button


Step 3. Open the QR-Code scanner by clicking on


Step 4. Point the camera at the QR code on the page



participation id instructions

How do I know the App is working?

If your app is installed and running, you will see a small ‘chart’ on the top of the phone or if you scroll down on the top menu.

working app instructions

How do I ensure that the App remains operational?

Please launch the App once every 2-3 days.

I just got an email from Leiden University requesting a ‘manual sync’, how do I do that?

Follow the yellow spots after launching the TapCounter App, but remember to be on WiFi or 3G or 4G internet while doing so.

manual sync instructions

I just got an email from Leiden University requesting my APP ID, what is it and how do I send it to you?

Please copy your APP ID from every Android smartphone and tablet that you (and no one else) use.



app id instructions

I just got an email from Leiden University requesting I re-instate the ‘Apps that can appear on top’ permissions, what do I do?

The simplest way may be to search ‘Appear on top’ or ‘Display over other apps’ into the search field of the settings. Click on that and then scroll to TapCounter and tun it on. See the steps below:

reinstate instructions

If this does not work, you can try this this:

reinstate instructions

The ’Apps that can appear on top’ setting may be called differently, for example ’Display over other apps’.

I just got an email from Leiden University requesting I re-instate the ‘Usage access’ permissions, what do I do?

The simplest way may be to search ‘usage data access’ or ‘apps with usage access’ into the search field of the settings. Click on that and then scroll to TapCounter and tun it on. See the steps below:

usage access instructions

If this does not work, you can try this this:

usage access instructions

What data is collected by the TapCounter App?

How much data does the App use from my data plan?

The App is designed to preferably sync the data when on WiFi, after multiple failed attempts it will tap into the 3G or 4G data. However, the data syncs are small ranging from a few KB to a few MB per month. That is, as small as a single camera snap captured using a smartphone per month.

What are the organizations behind the TapCounter App?

For this study, the research team at Leiden University is using this App. This App is operated by the University of Zurich Spin-off QuantActions AG (Zurich) and you can find its detailed privacy policy here. Google PlayStore and Apple AppStore are used to distribute this App to users like you.

How do I stop the App from recording data?

You can simply stop the App by uninstalling it. Note, to formally withdraw from the study please email us. To uninstall, long press on the App icon and click ‘Uninstall'.

stop app instructions