Let me get this straight. In June last year I thought my daughter, at the age of twelve, was too young have a smartphone. Then a mere four months later we bought her one. Was that hypocritical or did I just change my mind? I prefer to think the latter, but, anyway, that's not important right now.

Back in October, when our daughter became the proud owner of a new smartphone, I told her that now her father and I will be able to track her every move. I was kind of being mischievous. I was also attempting to signal that with great privilege comes great responsibility. Deciding to inflict the Find My Friends app on her was partly about trying to convey life lessons and partly about having a laugh. It sounded like a bit of fun.

Because we are an equal opportunities family, we told our daughter that it wasn't just about us watching her; we would all submit to being tracked by each other. My husband and I each downloaded the Find My Friends app to our devices but, because our daughter was too young to apply for an Apple ID, she was unable to get the app. How convenient.

Fast forward to this June. My daughter (now aged thirteen and in possession of an Apple ID) asked if she could download some music. Yes, she may. I also told her that there's no longer an excuse for her not to have the Find My Friends app. So she downloaded it and allowed us to access her whereabouts.


Last Wednesday around midday, I idly looked at the app then texted my husband. "Are you walking down Albert Street?" I asked. "Yes," he replied. "Spooky," I wrote. Impressed with the accuracy of the information, I looked for my daughter. Find My Friends told me she was roughly two blocks from her school. Surely not.

I texted her. There was no reply. So I drove to the location in question, and walked up and down outside the two houses the app was indicating. Then Find My Friends showed my daughter slowly moving overland towards her school. I got back in my car and drove to where I would be able to intercept her. While waiting, I received a confused reply to my text. "I was in drama [class]," she wrote. "No drama," I replied. (She was clearly at school. In all the excitement, I'd overlooked the fact that the school will text parents if a student goes AWOL.)

So that was a lesson in the vagaries of Find My Friends. On the one hand, I could actually track my husband as he moved through the city. Just minutes later, it provided misleading information about my daughter's location. A subsequent perusal of online reviews revealed that the information delivered via this app can be geographically imprecise. Yep, been there, got the tee-shirt.

I texted my daughter: "You should have seen me today. I was like: she's gone rogue. I'll follow her. I staked out a house and saw you moving closer to school. I was like: she's on the move. I'm on her. It was like Charlie's Angels!" (We watched an episode recently. It hasn't aged well.) "Haha that's so creepy," she replied.

Was it really creepy? It would be if anyone other than parents or caregivers did it. In the circumstances, it merely demonstrated concern. There's a school of thought that if you trusted your child you wouldn't even think of trying to track her. I don't buy that. My daughter gets full marks for being reliable and sensible but I reckon that most people (myself included) are just one poor decision away from going rogue.

And while my child is aged thirteen and operating a smartphone that wantonly drains my own data allowance, I reserve the right to keep her under whatever surveillance takes my fancy. Now, of course, I know that Find My Friends is for amateurs. Anyone serious about this mission is going to need to think about microchips and monitoring bracelets.

Later that same Wednesday I was due to meet my husband in the city. Waiting for him in the bar, I checked Find My Friends. If the app was to be believed, he was having a dip in the sea between two wharves on Auckland's waterfront. That was weird. He doesn't even like swimming.

• Join the conversation on Facebook and Twitter