Similar to Alexa by Bitscoop but instead of voice command on controlling the phone, why not create a voice command that would display the answers shown on "feedback" from google for you?
If you say "What is quantum mechanics?", the glass would display the "feedback" result shown on google. This would cover a wide spectrum of practical uses.
If someone say "What is the square root of 1000?", the glass will then display the answer gotten from google search result under the feedback section.