Do hidden apps exist on a non-jailbroken phone?

Hi everybody,

let me explain my situation.

So, today I was restoring my iPhone 4S from an iCloud back up through iTunes. First I just wanted to restore it to factory settings. I clicked on the restore button in iTunes, it gave me a message that there are some purchased apps on my iPhone that were not tranfered to my iTunes and would be deleted after the restore. I manually checked all of the apps on my phone, and they were all in iTunes, so that message kind of confused me.

After restoring the phone to the factory settings i chose to restore it from my iCloud back-up. Once the background restore has started, it asked me to enter a password for my Apple ID to install the apps as usually, but after several minutes another window popped up with some other apple ID requesting for a password. Now I can surely say that there were no apps that I know of on my phone that were installed from somebody else's account.

Now where this becomes interesting is that the person whose name was written in the apple ID box, once had an access to my phone for 2 hours without me knowing it. Also that person knew some of the texts that were sent from my phone.

Summarizing all of the said above, I got an idea that maybe that person had installed some SMS tracking software to my phone, which was hidden (it wasn't visible within the apps, neither has itunes requested moving it to my library).

My question is whether this is possible. My phone isn't jailbroken. And is there any way I can find it out using iExplorer (or something similar) by looking at my back-up file?(since the app shouldn't be there anymore cause i didn't know that person's password)

Does anybody know anything about this?

Thanks in advance.