As social media erupted with outrage over a sexism scandal at the app-based ride service Uber over the weekend, consumers in Seattle and around the country vowed to "delete the app" in protest.

But unless people followed that up with a tweet or Facebook post -- or entirely deleted their account with the company -- the message might not have been received.

"A developer is not notified when an application is deleted,'' said Morgan Reed, executive director of The App Association, a Washington, D.C.-based trade association that represents more than 5,000 app and information-technology companies.

"They may notice a decrease in information flowing from an app or reconnecting to their services,'' he said. "All it knows is that your application is dormant."

That's due to privacy concerns, and practical considerations that take into account multiple devices, new devices and user error, Reed said.

The company might also see a decline in use over time, he noted.

"We would not want anyone to delete an app, ever,'' he said, but doing so would not, on its face, send a message of protest.

What a company can see, however, are deleted accounts, and social-media posts. A spokesman for Uber could not say how many accounts were deleted as a result of the scandal. But there was no question about the backlash on social media.

The hashtag #deleteUber trended over the weekend after an engineer wrote a blog post describing a year's worth of sexual harassment she says she endured at the San Francisco-based company.

The engineer, Susan Fowler Rigetti, alleged that she and other women reported harassment to Uber's human-resources department, but their allegations went nowhere because her boss was a "high performer."

Uber's CEO, Travis Kalanick, on Monday hired former U.S. Attorney General Eric Holder and a partner at Holder's law firm to review the workplace issues raised by the blog, and the lack of diversity at the company.

"I believe in creating a workplace where a deep sense of justice underpins everything we do,'' he said in an email to employees. He added that he hoped the scandal would help "set a new standard for justice in the workplace."

Local reaction to Fowler Rigetti's blog was swift and harsh on social media.

"Yet another reason to boycott @Uber,'' tweeted Samia Dillsi.

"About to #deleteuber,'' tweeted Sydnie Jones, a Seattle-based writer. "@Travisk is lying, indifferent &/or incompetent. I hope you're humiliated and ashamed."

Jones said in a message that she hadn't deleted the underlying account, but that she would.

"I've only used Uber through the app, so it didn't occur to me,'' she wrote, "but I suppose it's not as effective to only deny them my business if they can technically still count me as a user."

Still, she said, "social-media pressure is so effective. I think it plays a bigger role."