I'm broadly not a huge fan (prefer to call in or go myself). But I also know that online ordering is contributing from a wide phenomenon of overworking and unreasonable expectations in kitchens (fueled both by customers and management). Particularly because most apps don't allow restaurants to cap orders per hour or otherwise indicate to customers how busy things are in the same, human way that calling in and having someone on the phone tell you, in their voice, that it'll be an hour because their busy does. The instantaneous experience of ordering masks the real work that goes on behind the scenes and allows people to ignore that labor even more than they usually do (which is why they get way madder if they have to wait 5 minutes in the restaurant when the order online).