The intensifying privacy battle between Apple and Facebook is coming to your iPhone screen.

Apple on Thursday released the latest version of its iPhone operating system, iOS 13, which includes a new feature meant to notify people when apps are tracking them in unexpected ways.

The first examples of the new notifications, which look like typical iPhone pop-ups, have circulated on social media and Reddit, where one iPhone user posted a screenshot after testing an early version of the new software. And they show the unfamiliar workings of some very familiar apps.

The user reported opening up Google Maps only to trigger this message: “This app uses Bluetooth to connect to and share information with accessories and other Apple devices."

Another screenshot shared on social media was about Facebook: “‘Facebook’ Would Like to Use Bluetooth: This will allow ‘Facebook’ to find and connect to Bluetooth accessories. This app may also use Bluetooth to know when you’re nearby.”

Phrases like those could quickly become familiar and even omnipresent for those iPhone users who upgrade their software to iOS 13.

Examples shared online have shown everything from Facebook and Google to digital media website BuzzFeed News setting off Apple’s notifications, a prospect that could make for a rude awakening for users who have taken for granted —or who’ve been kept in the dark about — just how much data companies collect on them.

The in-your-face warnings may help fill a gap in privacy. In December, computer scientist Aleksandra Korolova alleged that even if iPhone users had denied Facebook access to their location, Facebook was deploying Bluetooth connections and other workarounds to collect location data.

Using Bluetooth for something other than connecting to ear buds may alarm some users because that's not the intended use. The location tracking works by determining that another person's phone is in range, for example, or that a person is near a "beacon" device inside a retail store.

But privacy advocates aren’t necessarily convinced that Apple’s notifications will be effective.

“This is a step in the right direction, but it's still putting a lot of onus on users to understand and manage confusing settings,” said Justin Brookman, director of consumer privacy and tech policy for Consumer Reports.

“For most users, there’s very little benefit to giving Facebook access to location and Bluetooth, but many people just reflexively press ‘OK’ when prompted because they just want things to work,” he added. “As a result, they may still be unwittingly allowing themselves to be tracked in ways they don’t expect.”

One for @riptari - Facebook iOS app uses Bluetooth (without asking) to find out who is near you pic.twitter.com/dPcV4KH7HJ — Simon (@sieduk) September 12, 2019

The changes do, however, offer the most visible, consumer-focused example of Apple’s growing privacy push — and how that has put it at odds with other major tech companies.

Apple has met growing concerns over data privacy with an ad campaign touting the security of its phones. And it hasn’t been too shy about poking the tech industry. At the Consumer Electronics Show in Las Vegas in January, Apple — which famously does not attend the event — purchased a large ad to be displayed on a building near the show reading: “What happens on your iPhone, stays on your iPhone.”

The use of Bluetooth, which consumers typically use to connect their phones to wireless headphones and smartwatches, has particularly irked Apple. Craig Federighi, an Apple senior vice president, called the practice abuse at a company event in June and warned that Apple would soon be “shutting the door” on it. Tech news website Techcrunch on Monday called Facebook’s data collection “creepy.”

man, Safari is going to rattle a whole lot of cages over the next few months pic.twitter.com/innpwsLEVo — alex hern (@alexhern) September 11, 2019

Facebook declined to comment on the change by Apple, including the accusation that it had been abusing Bluetooth. Last week, Facebook released a statement telling users to expect changes in iOS 13 while arguing that “Facebook is better with location.”

Google did not respond to a request for comment. Apple declined to comment.

Precise location information through Bluetooth or other means is valuable to tech companies, including for advertising purposes. They may target ads based on location data, or if someone visits a store after seeing an ad, they may use documentation of the visit to tell an advertiser how well their ad worked — a process known in the ad industry as attribution.

Apple and Facebook have been squaring off on privacy issues for more than a year. In January, Apple said it had determined that Facebook violated its rules with a program that paid teenagers and others for their smartphone data, and some tech sector analysts believe there’s deep personal animosity between Apple CEO Tim Cook and Facebook CEO Mark Zuckerberg.