What do tech giants know about you? A new tool shows you just how much

From locations and home addresses to private messages and phone numbers - we give away precious private information to online services everyday and we do not even realise it. Yet we have agreed that companies can extract our personal data for their own use.

How many times have you read a privacy policy from an online software platform right to the end? Nope, me neither.

Fortunately online security platform vpnMentor has delved through the privacy policies of some of the most popular applications, creating an interactive tool that shows how these companies track our every move.

With over 7.2 billion accounts held across the services studied, including platforms like Google, Facebook, Amazon, and Tinder, how many of us are aware of the finer details of the privacy policies that we automatically accept?

Facebook and Instagram seem to be the biggest offenders, seemingly tracking as much as they can about their users.

Is it time that we thought twice about what we are accepting within the terms and conditions? Some of the surprising details tracked include:

• Location: Of the 21 services within the study, 18 tracked your current location at all times when using the app. Some of these, such as Tinder, continue to track this even when the app is not in use. Facebook and Instagram not only track your location but also the location of businesses and people nearby, as well as saving your home address and your most commonly visited locations.
• Your Messages: Do you think nobody will ever know about your DMs? Think again. Facebook, LinkedIn and Instagram use the information you share on their messaging services to learn more about you, while Twitter and Spotify both openly state they have access to any messages you send on their platforms.
• Device Information: Many services and apps track more of your device information than appears to be needed. Facebook and Instagram, track your battery level, signal strength, nearby Wi-Fi spots and phone masts, app and file names on your device amongst others. Google and Amazon keep voice recordings from searches and Alexa, and Apple Music tracks phone calls made and emails sent and received on the devices the service is used on.

If you do not hold an account with these services this will not stop your online moves being tracked. Google keeps track of your activity on third party sites that use Google features like adverts.

Facebook partners (8.4 million sites across the web) send both Facebook and Instagram data collected through Facebook Business Tools such as the Like button – regardless of whether or not you have a Facebook account or are logged in.

Adjust these Facebook privacy settings to protect your personal data

Even if you have set up the "Do Not Track" option offered by some browsers, which was created to stop sites tracking your information, you are not secure.Almost no major sites respond to the signal given, instead continuing to track you regardless.

It is not just third-party sites these companies are storing your data from, Facebook also holds any data provided about you from others – including those that upload your contact information without your permission.

Internet security expert Gaya Polat, from VPNmentor said: "The amount of data held online about users should make them wary about how their personal details are used.

While the majority of this data usage is benign or necessary for services to function, knowing which companies hold which data about you is the only way to track your privacy, and how secure you really are.

"We recommend always reading the privacy policy to ensure you know what you're agreeing to by signing up – but we hope this project will give something of an insight into what it all entails."

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