I spend a lot of time in coffee shops. I'm writing in Amsterdam, so let me clarify that I do mean coffee. I like coffee shops because: a) I like coffee, b) I find them relaxing, and c) and it is a way to be around people without the awkwardness of being obligated to talk to them.
It's very important to choose coffee shops wisely. Before I go on vacation, I always do careful research about where the best coffee shops are (again: for coffee). But "best" is complicated. You need to think about what aspects of the coffee shop experience are most important for your trip:
A) Quality of the coffee. The presence of single estate beans or fancy hipster brewing methods is a good sign, but it doesn't matter what equipment they have if they don't know how to use it.
B) Ambiance. How easy is it to relax? Or to concentrate? There's one place I used to go to often — closed now — awful coffee, but near me, and really cool decor.
C) Quality of food. Pastries only? Sandwiches? Hot food? How good?
D) Location, location, location.
E) Work friendly or people friendly? Some cafés you go to with a laptop, some you go with a group of friends. A book is usually always OK. Interestingly a tablet feels more to me like a book in terms of social acceptability than a laptop but maybe I'm biased.
I know one cafe where 24/7 there was always a row of six people staring at laptop screens. Nothing wrong with that, as long as you're bringing a laptop too.
F) Attractiveness of clientele. I never go to cafés specifically to pick people up, but it's always nice to be around people who seem interesting.
G) Staff. This is complicated because while nice banter will always make me smile, I am also happy to be left alone.
Happy to hear if there are important criteria that I am leaving out.