Spoiler Alert: Low Latency Crucial for Sports Apps

low latency sports

In the past, the only way to catch a big game was to tune in on network TV; for smaller events, cable or satellite television was necessary. But today, many Americans are “cutting the cord” and forgoing traditional television altogether: 24 percent don’t have a cable or satellite TV subscription. What’s more, 64 percent of cord-cutting Millennials say they don’t have a subscription because they can access the content they want online.

To keep up with these shifts in consumer behavior, major television providers—such as ESPN, FOX and NBC—now offer live-streaming sports apps, which viewers can use to watch their favorite teams through their smartphone or computer. And fans are responding: The 2017 Super Bowl broke records for live-streaming viewership through the FOX Sports GO app, with the previous record being held by NBC Sports’ broadcasts of the 2016 Rio Olympics. Akamai estimates 500 million viewers will soon be live-streaming primetime sports online.

With the massive audiences attracted by events such as the Super Bowl, World Cup and Olympics, live-streaming sports apps tend to have relatively higher latency. When thousands or millions of fans are trying to access a single stream simultaneously, latency is often injected to allow content delivery networks (CDNs) to cache content—so the same high-quality video stream can be delivered to users on a wide variety of devices and operating systems, with different connections and bandwidth.


Desktop vs. Mobile

There's also a notable difference in latency when these apps are accessed on mobile devices versus desktop computers. Desktop browsers have traditionally used the RTMP protocol with the Adobe Flash player plugin to deliver low-latency streams. But now, browsers are eliminating support for Flash, which will now have to rely on HTML5 or other licensed players, which can be used in any mobile or Web browser. In our testing, most of the desktop browsers defaulted to use Flash—so latency scores across the board were lower when testing the same apps on desktop than on mobile.

For mobile devices, the HLS is the more common delivery protocol. But without fine-tuning, HLS comes with greater latency; use a CDN, and even more latency gets tacked on. The end result: Live streams are delivered to some viewers with up to 90 seconds of latency. In the world of sports, where a 90-second lag between real time and stream playback can mean missing the game-winning play, the potential implications for the user experience (UX) are huge. 


High-Latency Sports Streams Are a UX Disaster

Spoilers resulting from high latency in live-streaming sports have a disastrous impact on the fan experience. Viewers may get calls and texts from TV-watching friends and family about plays their stream hasn't caught up with. And users who live-stream games while also monitoring social networks may read about the action before they see it—ruining the experience of enjoying the game in real time.

This was a problem with Twitter’s live-stream broadcasts of Thursday Night Football, when the platform’s own in-game tweets told viewers about plays before they happened. Twitter’s live stream ran 30 to 90 seconds behind the CBS TV broadcast, depending on the viewer's market. This all-too-common live-streaming scenario is every fan’s worst nightmare. While some end-to-end latency is necessary to maintain stream quality, apps must compete with traditional TV broadcasts to prevent spoilers. Cable broadcasts tend to have five to 10 seconds of end-to-end latency; satellite may be as high as 15 seconds. 

For die-hard sports fans, high-latency streams have a broad impact. For example, many fans place bets on games and events. Those live-streaming through an app want to be able to call their sports booker and bet right up to the last minute—or, in some areas, to place in-game bets through off-track betting establishments. Not only may streamers miss opportunities if their streams lag behind, they may place losing bets without even realizing it. High latency also affects fantasy sports players, who may struggle to adjust lineups, make player transactions or research changes in playing conditions and rosters if their streams don't keep up with the real-time action.

Perhaps most importantly, fans fork over a lot of money for live-streaming sports: The apps we tested require a cable or satellite subscription in order to watch most live events, which often run $70 to $100 per month. Fans who have paid a premium for apps that deliver a poor UX are likely to abandon the platform. And abandonment has a ripple effect for advertisers and broadcasters backing the app. A few high-latency streams can cause the leagues (e.g., the NFL or NBA) to take their exclusive redistribution rights elsewhere—to a network whose platform offers fans the low-latency streams they crave.

Facebook’s entry into the live-streaming sports market provides an additional threat to network-backed apps. Facebook recently made deal to broadcast some Major League Soccer and Mexican soccer league matches from its Facebook Live platform, and is negotiating with MLB to live-stream one weekly game throughout the 2017 season. Not only will viewers be able to comment, “like” and share in real time, Facebook will have its own graphics and commentators—offering a video-plus-interactive experience traditional broadcasters can’t yet compete with. 

So, how well are major live-streaming sports apps performing under these high stakes? To find out, we put several platforms to the test:


NCAA March Madness Live: Low Latency That Builds Over Time

One of the most popular apps this spring was NCAA March Madness Live, which delivered consistently low latency times for fans. The app offers video and audio live streams of each game, as well as VOD highlights and special programming. The platform's low latency facilitates some interactive features, as well: For example, in-game instant replays allow users to watch highlight clips seconds after a play, without interrupting the live stream. Other live features include a blog; scores, statistics and brackets; and notifications about favorite teams and important in-game actions. 

NCAA March Madness consistently performed faster for end-to-end experience than any other sports application. On desktop, end-to-end latency is nine to 12 seconds, while TTFF clocks in at three to eight seconds. On mobile, TTFF is four to five seconds.

While the average end-to-end latency for NCAA March Madness is low, in our testing, we found that latency on mobile devices consistently built up over time—that is, latency scores were generally higher at the end of a game than at the beginning (from 12 to 48 seconds). This could be the result of high demand, since many users are accessing the same app at once for a specified period of time; last-mile congestion; or stream interruptions, since each time packets are dropped, additional latency is injected as playlists are rebuilt by the players. 

Because it builds gradually over the course of the game, viewers may not realize this is happening at first. Even if their stream started with only a few seconds of latency, it could end at nearly a minute behind TV broadcasts—increasing the potential for spoilers during the game's crucial final moments. Luckily for viewers, when watching the app in full-screen mode, interactive elements are hidden from view. However, this issue is significant, akin to an athlete tiring out over the course of a game.

Coaches don’t want one player lagging behind the rest of the team—why should live streams be any different?


WatchESPN: More Games, Faster

As its slogan states, broadcast network ESPN has long been the “worldwide leader in sports,” and its WatchESPN app heeds that call. It's essentially tied with NCAA March Madness Live for the lowest desktop latency scores. 

On desktop, it scores as low as 10 and as high as 13 seconds in end-to-end latency, with four to six seconds in TTFF. On mobile, scores range from 29 to 31 seconds in end-to-end latency, and three to five seconds in TTFF. These low TTFF rates provide a good UX for fans surfing its myriad games and sports. However, WatchESPN’s average 31 seconds of mobile end-to-end latency may cause spoilers for die-hard fans following games on social media as well as through the mobile app.

WatchESPN offers the greatest variety in terms of the number of live sports and games offered, including coverage for more niche sports such as lacrosse, swimming and cricket. The platform also streams special athletic events; original programming; news and highlight programs (such as SportsCenter); and on-demand clips of game highlights and fantasy sports coverage.

Push notifications let users know when their favorite teams are playing so they never miss a game. Interactive features are also available—for example, social media integration, customizable news and statistics feeds and a built-in messaging function that allows users to send scores and updates to friends. A toolbar shows scores, highlights and previews of content playing live on other ESPN channels. Users can also watch both a live stream and a highlight clip at the same time, using dual windows. On app review sites, some users report issues with video quality; however, the app is rated well overall.


MLB At Bat: For the Out-of-Market Superfan

Next in our testing lineup is the official app of Major League Baseball, MLB At Bat. Desktop scores are comparatively higher than those of previous entrants: End-to-end latency is 32 to 63 seconds, with TTFF at two to eight seconds. Mobile scores are more competitive, with end-to-end latency ranging from 23 to 31 seconds, and a low TTFF at two to four seconds.

Interestingly, our testing revealed that desktop feeds on the West Coast were regularly eight seconds faster than East Coast feeds. Conversely, the East Coast mobile signal was an average of 4.5 seconds faster than the West Coast’s. For TTFF, there was no statistically significant difference.  

MLB At Bat scores with cord-cutters on one important factor: It doesn't requre a cable or satellite subscription to access live streams. Instead, streamers purchase a subscription to the app's MLB.TV feed—which is much cheaper. The downside is that users can only live-stream games that aren’t available in their market through another broadcast TV network, due to rights issues. 

Despite this, MLB At Bat provides a positive UX for out-of-market users by tapping into a unique aspect of baseball: the unique relationship fans have with their hometown announcer. With access to audio and video streams of games called by their local broadcaster, faraway fans can “root, root, root for the home team” as if they were in the stands. 

Interactivity is limited: Users can see stats, highlights and customizable notifications in the app, but not without leaving their current live feed. They can, however, switch between home and away broadcasts of live-streams, and there is a searchable archive of VOD replays. The biggest issue users report with MLB At Bat is perceived quality, primarily in the form of buffering and crashes. This can negatively impact the UX for fans who don't want to miss a single pitch.


NBC Sports Caters to On-Demand Viewers

NBC Sports has the second-lowest latency numbers in our tests: On desktop, end-to-end latency ranges from 26 to 28 seconds, with TTFF at four to five seconds. On mobile, it scores 40 to 57 seconds in end-to-end latency, while consistently averaging about four seconds for TTFF. 

The NBC Sports Digital division was the first to stream many of the highest-profile events in sports, such as an NFL game, the Olympics and the Super Bowl. NBC Sports has live-streaming rights to Sunday Night Football and some Thursday Night Football games, as well as the PGA Tour, the Stanley Cup final and the Tour de France. Higher latency is necessary to deliver high-quality live streams to huge numbers of concurrent viewers on different devices. Low TTFF is also important, since fans expect streams to load as quickly as changing the channel on broadcast TV. For short events, such as the Preakness Stakes—a horse race that’s only two minutes long—this metric is even more crucial, especially for viewers attempting to place bets.

NBC Sports offers some unique interactive extras, as well. For example, some events offer multi-camera views; races such as the Tour de France support live GPS and interactive maps; English Premier League soccer games boast a “Tactical Cam” that mimics a stadium-seat view; and commentary from social networks is integrated. Personalized tracking and real-time statistics are also supported.  

NBC Sports also focuses heavily on VOD, including clips and highlights of past events and previews of upcoming ones. The platform is also the only one, among the apps we tested, that offers full replays of events. Its low TTFF scores help provide a better UX for VOD watchers and surfers.

However, NBC Sports suffers from issues with perceived quality (a metric that relates to the quality of the stream and performance of the app). Users note problems with stuttering and freezing, and rate it lower than WatchESPN. Some fans watching Olympics coverage through the app were so frustrated by these issues, they stopped using the app entirely. To save lost subscription dollars, NBC Sports will need to improve perceived quality.


FOX Sports GO Is Last Across the Finish Line

FOX Sports GO has the highest latency ratings of the live-streaming sports apps we tested. On both desktop and mobile, end-to-end latency ranges from a minute and a half to nearly two minutes (87 to 110 seconds on desktop; 89 to 107 seconds on mobile). TTFF rates are lower: two to three seconds on desktop (the fastest of all apps), and five to six seconds on mobile. 

As mentioned, FOX Sports GO’s live stream of the 2017 Super Bowl broke viewership records. However, it went down during one of the game’s most crucial moments—causing some viewers to switch to a Spanish-language stream. Perceived-quality issues are not uncommon with FOX Sports GO: Many users report problems with poor video quality, and some say the app freezes or locks completely. Interactive functionality is limited, and only certain live events can be paused and replayed. One of the biggest reported drawbacks: Live streams of NFL games are unavailable on mobile devices due to rights issues. It also doesn’t offer streams of many local events, which may be problematic for fans who want to watch their favorite team from anywhere. 

However, FOX Sports GO does have the rights to regional Sunday NFL games, as well as niche sports such as Ultimate Fighting and Nascar. News, statistics and updates are offered through streams of programs such as FOX Sports Live, and notifications alert users when a game is about to live-stream. VOD clips and highlights are also available after broadcast. For multitasking viewers, the tablet version of the app allows for picture-in-picture live streaming. 

Notably, after a recent update, users now report better performance with the app . Overall, user ratings are still lower than for WatchESPN, and on par with NBC Sports. FOX Sports GO will need to improve its latency ratings even further if it wants to compete with the likes of WatchESPN and NCAA March Madness.



NCAA March Madness Live provides the lowest average desktop end-to-end latency in our testing—however, it experiences latency buildup over time. WatchESPN also offers low desktop latency, as well as a wide range of programming well-suited to sports junkies. MLB At Bat scores with the fastest TTFF and end-to-end latency delivery on mobile devices, allowing out-of-market superfans to cut the cord while maintaining their relationship with their hometown announcer and team; app stability may be an issue for users, though. NBC Sports caters to fans who want to watch big events, such as the Olympics, or VOD. FOX Sports GO lags in both latency and interactivity, but offers access to niche events, such as ultimate fighting. 

However, there is one thing all of these platforms must do if they want to compete with the likes of Facebook in the live-streaming sports market: reduce the lag between traditional TV broadcasts and their live streams. Spoil the action for fans, and they'll start cheering for a different live-streaming provider. 

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