I have nearly the exact same situation. I like being able to see when my mom is visiting my sister or some other place we used to go, and I like my mom being able to see what I'm up to, like when I visit museums or parks. Sometimes on a phone call she'll say "I saw you visited ...some place... so I looked it up online. Did you know ...something interesting about it...?"

But you can just mention those things when you talk on the phone ?!

Exactly my take. There can be a privacy and trust issue with tracking and location sharing, but the way my wife and I use it, it's a very casual thing so I can see if she's on her way home yet or something like that without having to have her text me while she drives.