If the application wasn't built properly for Glass (With a voice trigger and the development permission needed if using a custom voice trigger) it will install but you won't see it in the list of apps on the device, you can see more info in the link below:
There is currently no way for a user to view installed apps on Glass except using the main menu (Either by saying "OK Glass" or tapping to see the menu)
You can launch the activity using:
adb am start -n yourpackagename/.activityname
You can also try and use Launchy by Mike DiGiovanni which allows you to start native apps using the Glass interface