Apple has ended a multi-day row with Facebook and Google over their controversial spy apps.
The Silicon Valley giant restored Google and Facebook's enterprise certificates late Thursday, which brings an end to its ban on the company's internal mobile apps.
The ban left many employees unable to test early versions of software, or complete mundane tasks like book a shuttle to get around campus.
Many said Google and Facebook's offices were left in a state of disarray after their app permissions were revoked for less than 24 hours.
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Apple restored Google and Facebook's enterprise certificates late Thursday, which brings an end to a ban on internal mobile apps. Many said the move caused internal disarray at the firms
Users who 'consented' to take part in the program were instructed to download a 'Research VPN' app.
The app was previously referred to as 'Onavo VPN.'
After downloading the app, it showed a warning saying downloading the app would 'allow any app from this enterprise developer' to be used on your iPhone and may allow access to your data.'
But what it didn't explicitly say was that the app would collect all of their phone and website activity.
In addition, it would track what apps they downloaded, when they used them and what they do on them.
Earlier this week, Apple moved to temporarily ban Facebook and Google's developer permissions after both were found to be skirting the App Store's data collection policies.
Facebook and Google took advantage of Apple's enterprise certificate, which allows companies to test iPhone apps without going through the company's typical app review process.
Both companies claimed they did this to collect research on users' activity through an app sideloaded onto their mobile phone, as well as other devices.
However, the 'research' apps weren't supposed to be distributed using Apple's enterprise certificates, so Apple pulled their permissions, saying the apps had broken its rules.
Facebook was running a 'Research VPN' app downloaded by volunteers, some of which were teenagers as young as 13, and paying them $20 in exchange for tracking all of their phone and web activity.
Among the data collected from teens by the app was all of their phone and web activity, information on apps they installed, when they used them and what they did on them.
Google, meanwhile, had been quietly running a data collecting app called Screenwise Meter that pays users if they agree to have their activity tracked by the tech giant.
Facebook has admitted to paying young people to install a 'social media research' app which monitors their web activity, according to reports. Apple banned the app, formerly known as Onavo VPN, from the app store because it violated its data collection policies
After downloading the app, it showed a warning saying downloading the app would 'allow any app from this enterprise developer' to be used on your iPhone and may allow access to your data.' But it didn't explicitly say that it would collect all of their phone and web activity
Users sign up on the