Sure, there could be variations in prices based on the complexity of the question. In essense, it'd take Quora, Stack Overflow, AMAs, etc, and add a fee, plus near-instant responses.
One possibility based on the travel sector is to be a virtual tour guide, via WhatsApp, with live location sharing of the tourist. The person traveling posts questions in the form of words, pictures, videos and audio and the local person responds in real-time. Each inquiry costs very little (or is part of a package with a fixed number of inquires allowed), and the local can provide the service to many people in any given time frame.
An extension of the above: how about the traveler can ask how to say a certain phrase (or ask how to get out of a certain situation) and the guide sends an audio message in that language which the traveler can play for someone standing in front of them.
Or something totally different. A 5-second video/audio of my car making a strange noise, sent to the app's car community, and someone answers what it could be. Or you baked something and it came out looking odd and you can ask the cooking community, "what did I do wrong?"