Can a person use this secret mode to hide a tracker app without the phone owner knowing

[Android Central Question]

My secret security mode has a password that is set up. I know for a fact i did nit set this up cause 5 minutes ago is the first time i have even heard of it. So could my husband have put set my password to hide a tracking app on my phone?

 

[Rukbat]

Anything is possible, but if he did you have more problems than a security app on your phone.