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Progressive loading

Progressive loading

Progressive loading is a mechanism exclusive to ironSource that helps ensure a rewarded video is always available to play with zero latency, even just after another rewarded video closes.


Latency refers to the time between loading an ad and having an ad ready to show.

A delay can occur when the publisher’s request to fill the ad space with an advertiser’s ad isn’t met - typically due to a lack of demand from the ad networks in that particular moment.

It can take just a few seconds for the ad request to be filled, or it might not be filled at all. In either case, the end result is a poor user experience: the user tapped on the traffic driver, expecting to watch an ad and earn a reward, but is left staring at a blank screen for a certain amount of time.

Managing latency

Publishers have dedicated considerable time to optimizing their monetization strategy - typically through hybrid bidding and waterfall setups - to find the balance between sophisticated auctions and reduced latency. However, even the most optimized setup can’t deliver zero latency.

As a result, publishers generally choose from three approaches to manage latency’s impact on the user experience.

The first approach is to only show users a rewarded video traffic driver when there’s an ad ready to display. The second option is to always display the traffic driver, and if the ad inventory isn’t filled, users are simply left staring at a blank screen until they exit out. The third option is the same as the second, just with a slightly better user experience - if an ad isn’t available, a pop up will appear that states this.

The drawbacks of these options are clear, harming ARPDAU, the user experience, or both. That’s why publishers have dedicated considerable time to optimizing their waterfalls to reduce latency. Much of the focus has been on slimming down the size of waterfalls - a single publisher could have dozens of instances for multiple geos and apps, which delays the ad serving process.

However, running a highly optimized ship with only the best performing instances - while minimizing the impact on CPM from removing demand sources - requires manual upkeep. Even when executed well, zero latency is not attainable through traditional waterfall optimization.

Removing latency and saving time

With progressive loading technology - which currently is only available on ironSource’s mediation platform - publishers don’t need to worry about a poor user experience or the burden of latency management. Instead, they can focus on perfecting their rewarded video placement strategy, and maximize ARPDAU and retention as a result.

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