You're welcome. It depends; Life360 charges for additional places in one circle (for notifications), but if the user doesn't need many places then the app is good as free. There also may be features that certain users may not need, so they could only buy the features they want without having to pay for everything the app can offer. This seems better than having an app that is paid from the beginning, but that's just my point of view.
Hmm, Windows Phones can collect/determine and periodically save location data in the background in Settings > find my phone (check "Save my phone's location...") and if Location services (Settings > location) is also turned on. This means that the phone automatically and periodically determine its location even if an app isn't requiring location information. Apps similar to Life360 Family Locator (such as Track My Life) only get the information that was already determined by the phone so these apps do not significantly consume battery while they're running in the background (usually this information is mentioned in the app description in the store). However, since Life360 Family Locator has a "refresh" button, tapping on that can do two things: force the download of the latest saved location information of the phone (whether it be yours or someone else) or to force the phone to determine its current location and then send you that location. From my previous tests (me using Windows Phone and my girlfriend using an iPhone), her location is updated more frequently when she's using her phone - so this implies that the app is also only using the location that the phone has saved automatically (as opposed to determining the location live, like Waze, Maps, hiking and running apps).
However, (sorry for the long paragraph above), to answer your
first question on how much resources the app uses itself: there are two means that app uses power, while the app is "in use" (being viewed at the moment) and while the app is "running in the background" (e.g. while you're doing something else and the app isn't active/being viewed at the moment). You can see both of these consumption information for each app in your phone in the Batter Saver app. In my phone, Life360 Family Locator only consumes "<1%" of battery power while running in the background - not much - but it will become a different story if you keep the app actively displayed in the screen - all apps use most of the power this way (not while running in the background). If I frequently checked for the location of someone, e.g. every five minutes, then the app would have higher impact on battery life.
Waze shows the location of other "wazers" but not all of them. Although it's possible to monitor the location of someone specific from the app, I think you can only monitor one person at a time here. Try searching for Glympse - I use this to track or send my location to anyone, as well as the location of someone else
in real time provided that other person also has Glympse installed in his/her phone. The difference between Glympse and Life360 is that Glympse tracks in real time - so this app, even if it is only running the background, will definitely consume more power than Life360 when its tracking because 1) GPS antenna is constantly being used and 2) it has to send/download data constantly.
So: periodic checks for and then sends data = friendly on battery; constant checks for and sends data = not so friendly on battery.
Hence, for your
second question, yes location services can be turned off in Windows Phones, but I don't think a user can control the refresh rate. The phone uses a lot of mechanisms to determine the location (you may go back to post#2, second paragraph, second sentence). In addition, however, when the phone checks for its location (whether through GPS, WiFi IP or Cellsite triangulation), the phone only does it for a few seconds each time, so it may be reasonable to deduce that location services for periodic location tracking/saving doesn't significantly consume battery power. Furthermore, therefore, apps such as Life360 that only periodically check for location in the background also do not significantly consume battery power (hence only "<1%"), while apps such as Waze (even the default Maps app) will significantly consume power because they constantly check for location.
Waze is especially deadly, because it both checks for location and downloads traffic information in real-time - a lot of data, which means more power consumption. If ever I had to use Waze to check for traffic (and especially to navigate), I'd do so while plugged in.
