I've just purchased Portal for an elderly friend who doesn't even have a smartphone. One huge drawback in getting her connected to her (also elderly) friends is that Portal is dependent on a phone (albeit) connected via wifi only to be near to the device in order for WhatsApp to work. I think that for Portal to work best for older people, especially those that don't have a smartphone or do have one but aren't very familiar with it, it should be possible to get a WhatsApp account that is phone independent.