Want to launch your own HQ Trivia? Prepare for scale!

Geert Faber
Dec 7, 2017 · 5 min read

Large scale interactivity is in the spotlight. HQ Trivia has grown tremendously on iOS and has now teased an Android version. Meanwhile in Europe, Eurovision Junior Song Contest switched to a new online voting mechanism. However, with great scale come great challenges. At Ex Machina we manage play along trivia and online voting for many TV shows, often with hundreds of thousands of concurrent users. In this post we analyse the critical success factors and challenges for HQ and Eurovision and share our lessons on how to prevent you from these pitfalls.

HQ Trivia comes to Android

HQ Trivia teased on Twitter that their Android app is on their way for Christmas. After the rapid growth on iOS it’s the logical step to grow the number of players even more. A move that is welcomed by millions of Android users but not everybody seems to be too excited.

A number of people are afraid that adding possibly hundreds of thousands of new players will impact the game experience. Many players are experiencing lag and delays when too many players are trying to play along in the app. The video stutters or it’s not possible to answer the question before the timer runs out which fills the chat with complaints about lag.

And while it is priority 1 for the team behind HQ…

It still frustrates people when they can’t play along…

HQ is combining two very challenging technologies in a single experience.

  1. Low-latency live streaming
    Low-latency live streaming (<2 seconds) is difficult to scale to the number of viewers that HQ is experiencing. That’s why most live stream websites show 10 seconds or more delay. There are many different video standards that are used for live streaming. HQ Trivia is using a combination of RTMP and RTSP while other platforms are optimizing HLS or WebRTC to create a scalable experience. Low latency streaming is the only way to get the true ‘live’ experience and makes it possible for the host to quickly respond to results, chats and users.
  2. Large scale trivia and game mechanics
    The second technological challenge is scaling up the trivia gameplay. It needs to send the questions, register the user interaction, and provide the correct response. In addition it needs to show if a user got it right and how many players are left. All without providing questions and answers beforehand. Processing hundreds of thousands of interactions in split seconds and calculating results in real time can be a load balance and server challenge.

Prepare for peak traffic

HQ Trivia creates scheduled live events, very similar to live television. The challenge with scheduled live events is the extreme peak in traffic when the program starts. This can create heavy load on network and servers to make sure all users can connect, especially when these users want to answer questions or polls all at the same time. Other online services handle more interactions in total but over a longer period of time. Live scheduled interactivity can create extreme peaks of hundreds of thousands of interactions per second that need to be processed by the server. Additionally, the user wants to see if they were right, their new score and the leaderboard position.

Last week the European Broadcasting Union (EBU) hosted the Junior Eurovision Song Contest. It’s one of the biggest talent shows for kids that is broadcasted across Europe and Russia. As the EBU describes it “kids between 10 and 15 years of age compete for Europe’s most prestigious pop music award in the Junior Eurovision Song Contest”.

This year the organization introduced a new online voting platform that allowed viewers and fans in all European countries to vote for their favorite contestant. But when the voting started a large number of people had issues opening the site or casting their vote.

The EBU gave an explanation on Facebook and Twitter about the problems. Although they received 330.000 votes, they don’t mention the number of people that couldn’t vote.

But the damage was done and fans felt like they had an unfair chance to vote for their favorite.

The website was down for the majority of the voting period. It crashed under the weight of votes. Just admit it and cut the PR spin crap. — Facebook Comment

Besides the disappointment about the inability to support their contestant, people questioned the validity of the online vote in general.

In Poland it was not possible to vote on the internet because nothing worked. In Germany everything was fine. For me, the vote of internet users should be canceled — Facebook Comment

Creating a scalable and redundant environment that can support massive loads of traffic, balance this traffic over multiple servers and regions, and calculate real-time results requires specialized technology.

Our lessons from TV: Prepare for scale!

Over the years we have worked on many high profile applications for various TV shows around the world. From elections to quiz and trivia formats and talent shows. All of these apps are build on our scalable and redundant PlayToTV platform that is capable of handling 1 million concurrent users.

With this platform we hosted events that saw concurrency numbers that are unsurpassed in the industry. Making sure that servers can handle the capacity and keeping them from crashing is essential for Emmy winning TV formats.

The traffic traffic pattern from scheduled live events is different very different from many websites that receive millions of visitors. In a split second our systems go from 0 to 400.000 user that want to play-along, know their score, and see their leaderboards.

The image below shows the peak traffic for a weekly TV shows. During the week the traffic is minimal but when the broadcast starts everybody is opening the app at the same time.

So whether you are working on a new interactive and live format or if you are trying to recreate the succes of HQ Trivia, make sure you prepare for scale. Feel free to contact us if you want to know more about our scalable video and interaction platform.

PlayTrivia is the white label live trivia solution that blends questions, quizzes, and the live production into a single easy-to-use interface. Find out more about PlayTrivia on our website.

Want to read more? Check our lessons learned from broadcast television for interactive live streaming:

Or read how we can help you to launch your own interactive live streaming app:

P.S. Ex Machina is growing and looking for passionate developers, designers and project managers in Amsterdam , Rotterdam and Montreal. Check all open positions on our website.


The best insights from the Ex Machina Team. We develop innovative, interactive, multiscreen solutions for brands, media, and e-commerce companies. Our concepts, designs, apps, and platforms reach tens of millions of users, powering thousands of hours of interactivity worldwide.

Thanks to Jeroen Elfferich

Geert Faber

Written by

I work at @exmachinagroup and @ComingNextTV with media companies to create engaging and interactive formats. Predicts the @endoftelevision as we know it.


The best insights from the Ex Machina Team. We develop innovative, interactive, multiscreen solutions for brands, media, and e-commerce companies. Our concepts, designs, apps, and platforms reach tens of millions of users, powering thousands of hours of interactivity worldwide.

Welcome to a place where words matter. On Medium, smart voices and original ideas take center stage - with no ads in sight. Watch
Follow all the topics you care about, and we’ll deliver the best stories for you to your homepage and inbox. Explore
Get unlimited access to the best stories on Medium — and support writers while you’re at it. Just $5/month. Upgrade