Get Application Name/ Label via ADB Shell or Terminal
If you know the app id of the package (like org.mozilla.firefox), it is easy.First to get the path of actual package file of the appId,
$ adb shell pm list packages -f com.google.android.apps.inboxpackage:/data/app/com.google.android.apps.inbox-1/base.apk=com.google.android.apps.inbox
Now you can do some grep|sed magic to extract the path : /data/app/com.google.android.apps.inbox-1/base.apk
After that aapt tool comes in handy :
$ adb shell aapt dump badging /data/app/com.google.android.apps.inbox-1/base.apk...application-label:'Inbox'application-label-hi:'Inbox'application-label-ru:'Inbox'...
Again some grep magic to get the Label.