The GPS is standalone and doesn't need to be connected to a wireless network in order to work. Also, if the battery dies the time won't show up. If your battery gets low, the watch will warn you and then you can put it in power saving mode which will limit all functions and turn the screen to a grey scale which will prolong your battery use to several hours on even 5% battery. It's amazing. The first picture shows that I have 69% battery and on power saving mode it will last 4 days 8 hours. The second picture shows you what the power saving mode looks like. While enabled it will still give you notifications.