If Scream won't work until you open the app on your phone, Lookout was unable to connect to your device.
If Scream (or Lock or Locate, etc.) won't work until you open the app on your phone, Lookout was not able to connect to your device when you requested the Scream. This may have been because the device was either sleeping or on another screen beyond Lookout's. When you opened the app on your phone it connected to our servers, sensed the command there (Scream/Lock/Locate/etc.), and executed it. If Lookout isn't able to connect to your device some type of connectivity problem exists. It could be between our systems and yours, or something specific to your device.
For Android devices
Task Killer (task manager) or Battery Saver-type apps may be responsible for this type of problem. These apps see a Lookout process running in the background (which we do to keep you safe when you download a new app or are using Lookout's Safe Browsing) and incorrectly assume that this background process is unnecessary. If Lookout's processes are being terminated by a 3rd party app, our ability to execute the commands you ask Lookout to perform (Scream/Lock/Locate/etc.) is greatly diminished. But when you open Lookout, the Scream works—you are bringing Lookout into the foreground (it's on your screen), and our services re-initiate and connect to the Lookout servers to see if any commands are waiting to be run.
If you use a Task Killer or Battery Saver app, please ensure that you exclude Lookout from its purview so that we can consistently work to keep your phone as safe as possible. How you do this will depend on the apps you use, and we recommend that you read their documentation or send them a support ticket for precise instructions.
For iOS devices
If the device screams when you open Lookout, it's possible that you had the app closed when you originally requested the Scream. Open the Multitask Menu by double tapping the Home button. Scroll through the list of apps on this menu to see if Lookout is listed, then try another Scream. If it still doesn't work, please submit an email using our help form link at the bottom.