I have an old smartphone that was saved. The number I used on it was already canceled about two years ago.

I lent this device to an acquaintance. When she calls, can you see my WhatsApp conversations from that time? I didn’t format the device before I gave it to her. – Tatiana

Tatiana, “format” is a popular term for reinstalling the operating system on computers. It is not a very correct term and, in the world of smartphones, it can cause confusion.

On cell phones, video games and televisions and other “smart” devices, there are usually two procedures:

Data cleaning (reset, restoration): Simple and quick, the factory settings can be reset directly in the device settings and zero the data partition.
Reflash. Reflash reinstalls system files and readjust storage. It is only used when the system has been corrupted and is a rare procedure. In general, it is performed by technical assistance (it cannot be easily performed by the user).
The restore or reset procedure (also called “data wiping”) is effective in preventing the reading of old data from the phone.
Although “reflash” is somewhat more like the well-known “formatting” of the computer, you do not need to reflash before selling or borrowing a cell phone. So try not to get confused with the idea of ​​”formatting” your phone.

If you do not perform the restoration, your data remains stored on the phone and can be recovered at any time by the new owner of the device.

This includes your WhatsApp messages, emails, SMS messages, photos, installed apps, downloaded files and many others.

WhatsApp, on the other hand, even performs a local backup that can be read using appropriate software. Audio and image messages, especially on Android devices, can be opened directly on the phone’s storage without any obstacles.

As a long time has passed, your WhatsApp account must have been deleted and the sessions on some social networks must have expired, which will prevent login. However, there is a lot of data on the phone that a person can obtain if they are intent on doing so.

That is, the data is there, even if it does not always appear at first sight.

If you are concerned about the security of your data, you should never allow anyone else to use your smartphone without your supervision. Before selling or lending your cell phone for extended use by a third party, it is mandatory to restore the device to factory settings.

If you “did your homework” and set up a lock password on your phone, the new owner may have to perform a forced reset of the device. Depending on the phone model (especially the newer ones), the device cannot be used after forced restoration.