DNS

Beckham14 wrote:

Why would an android user took my iPhone 12 Pro and search private DNS for iPhone. Is my mobile phone is at a risk.

If an unauthorized person has had unrestricted access to an iPhone, it is unknown what settings or configurations or apps did or did not change, and is also unknown which credentials might now be compromised if any.

Usual would be restoring a pre-breach backup, and changing all credentials, passwords, passcodes.

The “an android user” is seemingly not relevant. What is meant by “search private DNS for iPhone” is unclear.

For your peace of mind you can check the DNS settings when connected to WiFi, by going to Settings > WiFi > [info button of connected network] > Configure DNS. This should be set to Automatic. If this was done when connected to their network, then you can choose to Forget the Network when it is connected and setting would change back to Automatic when connected again. If you were not connected to WiFi when this search happened, then no change could be made.

As stated before, the search for a private DNS is small compared to the breach that could have occurred by changing your password or sharing preferences if this was someone who you could not trust.