OS X and iOS grow more alike as the years go by, but OS X El Capitan veers away from its mobile counterpart when it comes to alerting you when an app requests your location. In iOS, an arrow indicator appears when an app is accessing your location. That same arrow indicator appeared in the menu bar by default in previous versions of OS X but not with OS X 10.11 El Capitan.
With El Capitan, you need to dig into System Preferences to get that arrow icon to appear when Apple's location services are being used. Here's how:
1. Open System Preferences and click Security & Privacy.
2. Click the Privacy tab and then click Location Services at the top of the list on the left.
3. Click the lock in the lower-left corner and enter your password to make changes.
4. In the box on the right that lists the apps that can use Apple's location services, scroll down to the bottom to System Services and click the Details button. (Also, make sure the checkbox is checked for Enable Location Services at the top, if you didn't enable it when you first set up your Mac.)
5. Check the box for Show location icon in menu bar when System Services request your location.
6. Click the lock in the lower-left corner to save your changes.
Now, when you are using one of the apps that you have allowed to access your location (from the list you scrolled past to get to the System Services line in Step 4 above), the arrow indicator will appear in the menu bar. And should the arrow appear seemingly out of the blue, you can click on it to see which app is requesting your location.
You can also view the list of approved apps from Step 4 to see which apps have recently requested your location. The arrow icon appears next to any app that has requested your location within the previous 24 hours.
Note that this arrow indicator doesn't cover any and all apps that might have requested your location. The Chrome browser, for example, uses Google's Location Services, and so anything you do in Chrome won't cause Apple's arrow indicator to appear.
(Via OS X Daily)