As Marcomura said, this isn't possible with Windows Phone the way that the apps are sandboxed and can't even be aware of each others' existence on the phone. But if you give us a little more information as to what your needs are, there may be a solution. For example, if you are wanting to let your kids use the phone to play games, but not be able to send a text message, you can use Kids' Corner. But even if that isn't your need, Kids' Corner can be used for other things with a little creativity. For example, I've seen posts where people use it to keep their games separate from other apps. You could use it to put apps in that you want someone else to use, but not have access to the rest of the phone.
There are limitations, though. While I no longer have Kids' Corner (and yes, you can rename it) set up, I did for a while for the grandkids, and IIRC you have to use the same PIN to unlock the phone in KC as you do normally, so you'd have to unlock KC and hand your phone to someone if you don't want that someone to have access to your whole phone.
If this sounds like it might meet your needs, I'd suggest first doing a search of the forums for Kids Corner and see if those posts help you, and if not, start a new thread with Kids Corner in the title to get appropriate responses. I'm sure that there are as many ways to use Kids' Corner out there as there are people without kids. :smile: