Apple has revealed the ways in which WhatsApp tracks the data of users and stores some pieces of detail about users around the world.
We've all suspected - and known - for ages that our mobile devices are checking up on what we do.
However, WhatsApp has made a point of stating over the years that they are the most secure messaging app going.
It is definitely the least invasive of all the services owned by Facebook, but that isn't going massively far, when you think about it.
Also, it's worth assuming that all apps are mining your personal data in some shape or form.
WhatsApp tells you about what personal data they keep on you in the terms and conditions that you were supposed to read when you signed up, but who has the time to do that, right?
Now, the folks behind the iPhone - and crucially iMessage - have shined a light on the information apps are actually grabbing from you.
On 14 December last year, Apple introduced new privacy labels that explain what data every app in the App Store is harvesting from you.
When you look up an app, a label is shown that tells you exactly what data it will be collect. This includes Apple's own products.
According to that, WhatsApp takes info such as contacts and location from you.
It could also get hold of your email address, financial information, phone number, and user content. That could all be linked to your identity.
Before Apple's scheme was rolled out, WhatsApp criticised it for being too vague.
The company said it doesn't tell the full story and isn't representative of how far the developers have gone to ensure that personal information is protected.
It said: "While providing people with easy to read information is a good start we believe it's important people can compare these privacy nutrition labels from apps they download with apps that come pre-installed, like iMessage.
However, it's not completely blameless. Some of the tags are deserved.
Data on purchases is later shared with Facebook to influence the things that will be targeted at you as advertising.
As WhatsApp says in its privacy policy: "Facebook and the other companies in the Facebook family also may use information from us to improve your experiences within their services such as making product suggestions (for example, of friends or connections, or of interesting content) and showing relevant offers and ads.
"Facebook will not use your WhatsApp messages for any purpose other than to assist us in operating and providing our Services."
