Is it possible to record screens of two android phones connected to a PC? I am new to Mobile testing, Recently started using Android adb and started recording device screen using adb shell screenrecord command. Just wanted to know if we can record screens of two android phone at a time connected to a same PC using adb.
Execute adb help and notice 

-s           - directs command to the device or emulator with the given
               serial number or qualifier. Overrides ANDROID_SERIAL
               environment variable.

Serial number can be found from adb devices. For example, 

bash-4.X# adb devices
List of devices attached 
543b45da        device

543b45da (imaginary here) is the serial number for my device.

Serial number can also be found in the output of adb shell getprop or the file build.prop under /system. Look for the term(s) ro.boot.serialno or ro.serialno.

Now that you've the serial number, simply do

adb -s SERIAL_NUMBER YOUR_COMMAND/ADB_ARGUMENT


E.g.

adb -s 543b45da shell getprop


You can execute command(s) for multiple devices from multiple terminals simultaneously. The answer by moonbutt74 may also help.