Is it every 10 minutes?
I haven't downloaded the app myself. However, I was under the impression the 'virtual walk' was some separate feature that when turned on, allows the person to monitor your whereabouts in near real-time. (like could watch a tiny dot moving on a map as you walk).
One update every 10 minutes is way too infrequent. I feel like the majority of walks people could use this with would take less than 10 minutes ...
I go out for mega long bike rides in areas with very spotty cell coverage (Silicon Valley). This app is great because when my spouse wants to know where I am she can initiate the request, and I can keep my hands on the handlebars and keep rolling. I only wish they had thought to allow choices other than 'phone ring, wait 5 minutes'. I'd have prefered to set the notification type and delay. I hope the GPS battery drain for this feature is low (as compared with Garmin Connect, Strava or Glympse). 10 minute intervals sounds great.
Waiting 10 minutes for a GPS update doesn't seem to actually increase safety in any noticeable way.