South Bay family perplexed by $13K bill over half-hour of phone's internet use

An airplane passenger uses a phone while on a flight. An airplane passenger uses a phone while on a flight. Photo: Pojcheewin Yaprasert / EyeEm Photo: Pojcheewin Yaprasert / EyeEm Image 1 of / 1 Caption Close South Bay family perplexed by $13K bill over half-hour of phone's internet use 1 / 1 Back to Gallery

A San Jose family was feeling upbeat upon their return to California from an annual reunion with relatives in Vietnam — until they received a shocking $13,470 phone bill from T-Mobile.

Vivian Chung had thought her family was covered from high fees while they were overseas, but apparently, roughly a half-hour of phone usage while in the air had caused a massive charge.

Her son, Nicholas Ho, told KGO he had used his iPhone to play a game during a flight coming into Vietnam. But here's the thing: he played the game offline, while the phone was in airplane mode.

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"How can this phone bill, like $13,740.19 in one half hour?" Chung said in an interview with KGO. "Oh my god, we almost fainted. I say this costs more than the trip."

The family reached out to T-Mobile, but the carrier was not especially sympathetic. The company reportedly told them that their son must have downloaded a movie. T-Mobile reduced the bill to $3,800.

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KGO, as part of its "7 on Your Side" segment, dug into the ordeal on the family's behalf and confronted T-Mobile about the charges. The phone carrier only said that Vietnam wasn't included at the time in the free roaming T-Mobile plan the Chung family thought they had. After doing further research, it became clear that the game app that Ho played was using data in the background for ad and software purposes, even while the phone was in airplane mode.

T-Mobile wound up clearing the charges.

It's not a problem limited to T-Mobile customers or even American smartphone users. Consumers with Verizon and other carriers have reported spikes in data overuse stemming from similar apps that update in the background without their knowledge.

It is an issue that can be easily avoided, at least while still in the United States. Follow these steps for iPhone or Android to limit background data use.

Alyssa Pereira is an SFGATE staff writer. Email her at apereira@sfchronicle.com or find her on Twitter at @alyspereira.

