and I didn't have to install something or pay for something
How to set that up
"Did you know that Android has a built-in mechanism for locating or locking your lost phone? Google hasn’t done the best job marketing it, but it’s actually been baked right in since the release of Android 4.4*.
(It works with older Android phones, too — you just have to install the free app yourself)
Today that feature gets even better, thanks to the addition of a trick that seems so obviously great in hindsight: your lost phone can be set to call you — and only you — as soon as someone finds it.
If you lose your phone, just head over to Google’s browser-based Android Device Manager. Tap the lock button, toss in a “Recovery Message” (read: a plea to whoever finds the phone to not be a jerk) and an unlock password, and add a phone number where you can be reached.