From time to time, I have an uncommunicative guest, who had registered the landline as his airbnb contact info. That's quite annoying, as you cannot send an sms with the automatic feature on your phone, Contact / Call or SMS. You may call their empty home however.
Instead, you have to hunt through a long thread of messages (this type of guest requests a very long correspondance in the four weeks before a single night), to find their mobile phone, if they have given it. If you find it on the thread, you can't copy it in the phone function, as the whole message is copied.
I suggest, that airbnb prompts members to set their mobile phone as first registered phone, even hosts. (They do travel one day)
And explain, that the normal function of airbnb system requests them to be reachable during their trip.
In the same sense, I would like, if the app downloads all the contact info and details of current and future stays, to delete it from temporary storage only a week after a stay.
If you have a lot of pending trips and someone sends you an sms on the street, sometimes you have not all details in memory, but it would be great to look them up without using phone data, to be able to answer. For guests it's even more important, they arrive on an airport and have no local phone data, but most can send an sms. Besides, it's cheaper to look up everything on the app memory, switch on the data for one check of emails and to send one text, then to use data to check long known facts.
Today, if you open a newspaper app, all the articles on your choice of chapters are downloaded and stored on the phone or tablet. If you read them offline, you have no big pictures, but you have the texts, thumbnails and style elements of the pages.
I believe the details of reservations already checked that day stay available already, but not for the reservations, you did not check recently.
Guest need access to booking confirmations, messages with arrival data, host phone numbers for all reservations of a trip, to plan correctly.