When Apple or an application uses your iPhone's Location Services feature, a tiny arrow appears on the upper-right corner of the device. This icon reminds you that its whereabouts and usage are being tracked in order to give you the location-based support you've requested in real time -- for example, turn-by-turn driving directions. Though convenient, there are privacy implications to enabling Location Services. The little arrow helps you stay vigilant.
Your iPhone regularly updates its approximate location using nearby Wi-Fi, cellular, iBeacon and GPS networks. Location Services enables you to restrict or share that information -- and other location-based data -- with others. When you activate Location Services on your iPhone or apps, you enhance their capabilities. For example, a location-enabled Reminders app could send you geofenced reminders triggered by your arrival at the office. In some cases -- such as with the Find My iPhone app -- Location Services is essential; without it, the app can't help you find, much less wipe and lock, a lost device.
Location-enabled apps and services track your iPhone by periodically querying it for location-based information. They may do this while being used or running in the background on your device. A little arrow appears on the iPhone's upper-right corner to advise you when data is shared. Arrows also appear within the Location Services settings screens to indicate when and what kinds of information was shared with whom.
You can configure many aspects of Location Services directly on your iPhone. Tap "Settings" followed by "Privacy" and "Location Services." You may toggle the main "Location Services" switch to "Off" if you're not comfortable sharing your location with anyone, but understand that some apps may not perform properly or at all afterward. Alternatively, activate Location Services and allow only specific apps to access its data; toggle their individual switches to "On." Note that a location-enabled Safari app may also permit websites to track your location.
Tap the "System Services" button to regulate Apple's use of your iPhone's location-based data. Toggling any switch to "On" permits Apple to do two things -- support you with one of its massive crowd-sourced location-related databases, and collect your own location and usage data for anonymous inclusion into that databank. Here's what you'd get by activating displayed options: faster cellular connections with Cell Network Search, true north on your Compass app with Compass Calibration, warnings about weak-coverage areas with Diagnostics and Usage, geographically relevant ads with Location-Based iAds, popular apps in your area with Popular Near Me, time zone adjustments with Setting Time Zone, current road conditions with Traffic, nearby hot spots with Wi-Fi Networking and predictive commute planning with Frequent Locations.
By providing arrow alerts and numerous setting controls, Apple has taken measures to make the use of Location Services on your iPhone as transparent and granular as possible. Still, it's important to carefully review the privacy policies of those you would permit to track your iPhone whereabouts or usage. Learn how your location information will be shared and protected.