Seriously though, you have 40 seconds. On the outside. I have a slow old 3GS and it takes me a few times to get the pic right, but I can still get a pic taken, write a quick caption, and ironically #hashtag a picture within that timeframe. Hurry up.
I am the second to admit that I have a problem with pulling my phone out in social situations. But I can at least put it back in my pocket relatively fast, even if I pull it out again three minutes later. I get the compulsion to check it when it buzzes and share things you think are worth sharing - just stop taking 10 years.
The best type of mobile experience should be over in seconds, something Microsoft understood but couldn't make a good ad out of. There are times when I want to be wholly devoted to my phone - on the bus, to reuse the case I always pull out - but most of the time I don't want to be staring at a small glowing rectangle, I want to be doing stuff. That stuff might involve checking Twitter real fast or replying to an email, but this shouldn't take minutes out of my life, it should take seconds. Instagram, somewhat necessarily, takes a few steps - getting the photo right, deciding which filter is the least hideous, tossing up whether to push ANOTHER photo to Facebook. Whenever I've held my phone up for longer than five or so seconds, people make an overplayed joke about how lame Instagram is; I do this too, it's just such a transparent process.
The obvious solution is to just stop taking photos of everything that looks remotely shareable (for the record, I'm not too bad at spamming Instagram), but it's 2012 and that argument is lost. At this point, if you are the kind of person who needs to Instagram every gathering, just get it over and done with fast. Smartphone roulette is silly, but its base assertion that we need to get the eff off our phones and talk to each other isn't. Hence my rule: if you are getting out your phone while in conversation and it isn't urgent - you get 40 seconds. I won't complain or anything after that - god, I'm not a pedant - but I try to stick to it myself. Smartphones are great, but they are also really, really bad.
Am I lowballing it here? Should you be done with the filtered photo in 20 seconds instead? Are smartphones slowly killing human interaction or just kind of annoying? The latter, obviously, but you still gotta watch out.