https://www.youtube.com/watch?v=8SO8KcfhJmc
Old school methods like what McDonald's use, literally allow the customer to see in to the kitchen are very effective.
Not always ideal for every type establishment but I've seen high end Indian restaurants even do it by having the POS at the back where you can see the kitchen when paying which keeps the noise separate for the desired quiet atmosphere of a fine dining restaurant
I'm not sure how to translate this to the smartphone market though. Fairphone and LaJolla seem to do well in this regard though so back to brand reputation for a lot of this.