"Top 15 Mobile & Tablet Police Apps" - CriminalJusticePursuit
10-21 (radio code for "make a phone call") is a Police App for making free* calls to citizens that GET ANSWERED. Calls are made from local (not blocked) numbers without revealing your personal number. Stop getting sent to voicemail!
For example, if you call a citizen in Miami area code (305), they will receive an incoming call from a local (305) number, regardless of where you are. They are more likely to answer that call on your first try.
If the citizen calls back, rather than bugging you off-duty, they will be prompted to "Press 1 to Request a Call Back" (via Push Notification) or "Press 0 to Reach a Dispatcher" (connects to a non-emergency number that you provide).
When citizens request a call back, you receive a Push Notification on your phone rather than a phone call. At your convenience, simply tap the notification to initiate a call back out to the citizen.
*Calls are made over a VoIP data connection and do not use your cellular minutes. While the data used is minimal, data usage fees from your provider may apply.
Update: Android 6.0 Marshmallow Users - Permissions Issue FIXED in Latest Version