This story does little to explain how it will actually work for people in Canada that already have a cellular plan with someone other than 'the chosen one'.
Will you have to remove your SIM card and install the 'special one' to use it during flight for free texting? The odds of losing your SIM card go through the roof if you change out your SIM card on an aircraft. Then there's the chance static discharge damage occurring during flight because we all know how dry the air can get during flight in the cabin.
Why not have free Wi-Fi onboard instead for those passengers instead and then then can use their own phone with their own plan to make text and calls over Wi-Fi?
This whole article leaves one with more questions and doubt about the actual programme than it answers.
Hopefully, a detailed update on this 'free service' will happen soon.