NPO Live App

Live sync with watermark technology


Commissioned by the NPO, the already existing NPO catch-up app (also designed and developed by Stoneroos) is expanded
with a very interesting update. The audio synchronisation function is added to the app. This means that the app
receives the exact timestamp of the first screen, using this to synchronise the app to the first screen.
Therefore, both screens are perfectly synchronised, no matter what the delay of the first screen is.
And this offers a lot of possibilities for the users, program makers and advertisers.

How it works and what we’ve done

In the live broadcast signal of the NPO channels, Civolution’s watermark technology is integrated. This watermark
contains a timestamp, which is being picked up by the NPO app. The timestamp and the broadcast signal will then be
compared and the right screen will be formed in the app. Enriched EPGdata, second screen applications, websites,
social media, related on-demand content, information about the (next) program, etc.; all this information is being
connected to each other and processed into a very organised and clear screen. By picking up the exact timestamp
trough audio synchronisation, the app is exactly in sync with the first screen. Ideal to develop second screen
features, like play along games!

Detecting and synchronisation

On top of the screen, there is an icon that shows whether the app is searching (listening) for the right channel.
This function, of course, can be turned on or off. When the app recognises one of the channels (NPO1, NPO2 or NPO3),
it will be perfectly in sync with the first screen, using the timestamp. The corresponding screen with all the
relevant information will automatically open. Also, all the catch-up episodes off the program will be shown in a list.
These episodes can be watched easily by clicking on them.

Embedded second screen apps

In the app, there is a environment for second screen applications. If the app detects a second screen for a certain program, it will be shown there. When a program maker wants a second screen that is perfectly in sync with the first screen, this can be added in this environment. For instance a play along game, a quiz or some background information. Of course a full screen function is available for this feature.

Or go full screen with your second screen app

The message centre

In the message centre, all the relevant information of the program will be shown, like a website or social media feeds. Also, information about the programs on the other NPO channels or information about the (next) program is shown here.

Synchronised commercials

The Ster (dutch marketing operator) is fully integrated in the NPO app. During every Ster-block the app will show exactly what commercial is broadcasted, how long that commercial is still airing and what the next commercial will be. Because this is always fully in sync with the first screen, this offers ideal possibilities for advertisers to strengthen their advertisement! The Ster Extra acties are a perfect example of this.


What we have to offer

With a history in the public broadcasting, Stoneroos has a lot of experience and feeling in creating television
and the surrounding concepts. Add this to our inhouse design and develop capabilities and you’ve got a golden combination. Because we always strive for high quality and unique apps, we challenge our designers and developers to go for
the perfect user experience in a stable and well developed app.


From consulting about the best audio sync technology to developing the first concepts, Stoneroos was very involved with the project, even at the very beginning.


Functional Design

Based on the chosen concept, sketches and scenarios, we’ve developed wireframes and flowcharts to let the user use the audio sync technology and all the fantastic extras made possible by this technology, without any worries.

Interface Design

The new NPO companion app has a totally renewed lay-out. Based on the NPO’s branding, Stoneroos used her own experience in developing apps to create a intuitive, stylish and user-friendly app.



Our developers developed the front- and backend of the NPO app. The interface, picking up the watermark signal, adding extra content like second screen apps and enriched EPGdata to the programs; we did it all.

The Live Sync functionality is an addition to the NPO app

Already, Stoneroos was responsible for designing and developing the NPO catch-up app. By clicking the link you can see how that project was realised.



  • NPO

Our services:

  • Back-End Development
  • Concept Development
  • Front-End Development
  • Interaction Design
  • Interface Design