Unable to start the Appium Server in pre-launched mode

Support
1

1.Set the IP address and Port no.
2. My device is connected (Verified using adb devices command)
3. Start the appium server.

But its not getting started and showing error “No app set; either start appium with --app or pass in an ‘app’ value in desired capabilities, or set androidPackage to launch pre-existing app on device”

Running test on real devices.
Android Studio installed.
Appium Ver 1.3.4.1

FYI: I am trying to pass the apk and other things using DesiredCapabilities

LOG

Starting Node Server
info: [debug] Starting Appium in pre-launch mode
error: No app set; either start appium with --app or pass in an ‘app’ value in desired capabilities, or set androidPackage to launch pre-existing app on device

Node Server Process Ended