Is free wi-fi widely available at the airport? We're flying in to Bangkok next week and sister in law will pick us up at the airport. She lives near the airport so we plan to call her when we are at baggage claim so she can leave home to come and collect us. Is there free wi-fi available in the arrivals hall / baggage claim area? We'd prefer not to use our phones from home as the charges to use it overseas are "pang". I have seen the long queues at the telecom stores to get a local Thai SIM card and after a long flight we'd rather wait until the next day, hence the question.

Yes, they have free wifi, and for me it has been working in the past, sometimes quite slow, but good enough to send a message to let her know that you arrived.