Phone apps that expose Stingray surveillance

Use these apps to expose cell phone surveillance:

SnoopSnitch
https://play.google.com/store/apps/details?id=de.srlabs.snoopsnitch&hl=en

Android IMSI-Catcher Detector
https://secupwn.github.io/Android-IMSI-Catcher-Detector/

F-Droid
https://f-droid.org/repository/browse/?fdid=com.SecUpwN.AIMSICD

Pwnie Express alerts businesses and home owners if the gov't is using Stingrays.
https://www.pwnieexpress.com/

Click here to find about more IMSI catcher/detectors.

Private cell phone apps:

Signal
https://itunes.apple.com/us/app/signal-private-messenger/id874139669?mt=8

TextSecure
https://play.google.com/store/apps/details?id=org.thoughtcrime.securesms&hl=en

RedPhone
https://play.google.com/store/apps/details?id=org.thoughtcrime.redphone&hl=en