When it comes to loading mobile networks with signaling traffic, the popular Angry Birds mobile app on Android devices looks more like Hitchcock's The Birds to operators. (See Operators Urge Action Against Chatty Apps .)

That's because the gaming app generates significantly more signaling traffic on devices based on Google (Nasdaq: GOOG)'s Android OS than on other smartphones, including Apple Inc. (Nasdaq: AAPL)'s iPhone, according to recent tests conducted by Nokia Networks ' Smart Labs.

NSN found that when measured against their smartphone baseline of 688 signals sent to the network per hour, Angry Birds on an Android-based Samsung Corp. Galaxy smartphone, with mobile advertising, generated 2,422 signals in one hour of play, which is a whopping 352 percent increase. By comparison, Angry Birds on an iPhone with no advertising generated 8 percent more signaling traffic than NSN's smartphone baseline after an hour of play.

The main reason for the significant difference in signaling traffic is the addition of mobile advertising in the Android Market version of Angry Birds, according to Leslie Shannon, NSN's marketing manager for mobile broadband. Each time a player reaches a new level in the game, a mobile ad is delivered that requires a network connection, she explained. "You can see the effect this has on the network," she said.

Angry Birds creator Rovio Mobile Ltd. is aware of this signaling issue. Rovio founder and "Mighty Eagle" (yes, that's his official title) Peter Vesterbacka told Light Reading Mobile at the Open Mobile Summit in London last week that his firm is working with NSN and taking steps to optimize the mobile app.

"We want to make sure we're a good ecosystem citizen … we want to play nice," Vesterbacka said. "So, operators will, let's say, not create any problems.

"There's a lot we can do in the app [to resolve this problem] and we can do it faster than the handset manufacturers," he said.

Why this matters
Angry Birds is just one mobile app, but this example shows how apps can behave differently on different smartphones when it comes to the amount of signaling traffic they generate.

It's this unpredictability that operators are struggling to deal with as certain apps and devices cause erratic spikes in signaling traffic on their networks -- sometimes with the ultimately devastating effect of making voice calls impossible. And the troubles with signaling traffic are a key reason why operators have recently started talking about the need for better cooperation with apps developers and device manufacturers.

For more
Coping with signaling traffic load, while not the most glamorous of subjects, is an important issue for mobile operators today.

— Michelle Donegan, European Editor, Light Reading Mobile