May 27 2022: A study by Virtual Private Network services provider Atlas VPN, reveals  the extent to which technology giants  like Google, Facebook, Twitter, Amazon, and Apple collect information about its users. Google collects the most, Apple the least.
The primary data was collected and made public by the Security.org team, which read through the privacy policies and extracted the data points. Atlas VPN summed up collected data points for each company to provide an easy-to-digest overview 
Google
A quick glance at the chart shows that Google takes the top spot in regards to the amount of data collected as they log 39 metrics about each user. In general, they collect every little detail that they can. There are a few exceptions, like your address, SSN, or driver’s license number, but besides that, not much else is left out of their databases. They gather your name, phone number, payment information if you have made any purchases through Google, email address, emails you send and receive, films, photographs, documents, and spreadsheets you have stored, and your Youtube comments. On top of that, Google records your search keywords, video views, and interactions with content and adverts. Even calls made through Google are not private since Google records calling and receiving party numbers, forwarding numbers, call times and dates, call durations, routing information, and call types.
Twitter
 Twitter collects 24 data points for each user. Unlike Google, the popular social media platform keeps very little personal information; they only end up with your name, username, password, phone number, and email address.
Besides that, Twitter maintains track of your messages, content, videos you have watched, views, and interactions with content and adverts. They will record the time, frequency, and duration of your Twitter activity, as well as the people with whom you engage and share material.
Amazon
Amazon is just slightly behind Twitter in data points collected, with 23 per user. 
For personal information, Amazon logs your name, username, password, phone number, payment information, shipping address, and email. Nothing out of the ordinary for the most part since it is an e-commerce website, but there is one caveat - they collect your social security number and driver's license information. Amazon also  sources data about your credit history from credit bureaus.
Facebook
To put it mildly, Facebook had a few issues with how they use their user data. Perhaps because of those issues, they currently collect only 14 data points.
On the other hand, the data they collect is extremely sensitive. Facebook keeps track of the people you talk to, the groups you belong to, and even your private messages. Facebook knows when you log on, for how long, and what comments, shares, and transactions you have done during that time.
Apple 
Likely little to no surprise for privacy enthusiasts, Apple takes the cake when it comes to user privacy. They only keep the information necessary to maintain your account.
They collect 12 data points and know their users' names, email addresses, IP addresses, location, and payment information. They mostly stand out in the department of activity logging. Apple knows your search queries, the time, frequency, and duration of your activity, and that is basically it. 

No matter which company you choose, they store at least some information about you and your activities. However, some, like Google, base their whole business on data, so they collect everything under the sun.
Others, like Apple, earn most of their revenue from selling expensive hardware, which allows them to log only as much data as is necessary to uphold your account. In short, Apple is the clear winner when it comes to privacy. 
Read the full report, here.