I have an HTC One S but I don't know where it is. I remotely installed 'Find My Phone' on it via Google Play Store. Now I want to remotely launch it. How can I do that?
Although there is not a general solution for remotely launching apps, here is a solution that applies to your situation:
First, install AndroidLost from the online Google Play Store.
- this is the app you can use to control/wipe/access info about your lost device, yadayada
Give it a little time to install to your device, then install AndroidLost Jumpstart from the online Google Play Store as well
This app will wake up the registration process on the androidlost app when ever a phone call is made, an SMS received, battery is low, a package is added, removed or changed.
So you have to install an arbitrary app from the Play Store as well to activate the service, but you can then go to androidlost.com to access functions to control your lost device! Including ringing an alarm ;)
EDIT 2015-01-29: Jumpstart won't help on a device with Android newer than 2.x, as in the description you can read: "Please note that google has changed the android API so this app only works on android version < 3." So not possible with a phone with 4.x to register AndroidLost later, without the physical possess of the phone.
If GPS accuracy is enough for you, Plan B is just what you need. You can remotely install it via the Play Store web interface and it activates automatically, sending the phone's coordinates to your primary Google account.
However, it can't play sounds on your device to help you narrow the location further.
Assuming that you haven't changed the default triggers for the app, you can simply text your phone from another device with:
findmeto get your phone to send you GPS information about it's location
ringaloudto get your phone to send you GPS information about it's location and to ring out loud at full volume.
Sourced from their instructions page.