There is a small, slightly weird, almost entirely overlooked genre of consumer software whose entire business model only works if you leave home.

Most of the software in your life is at war with the real world.

That is not a moral claim; it is a structural one. A feed-shaped app is engineered to be the most rewarding surface in your field of vision at any given moment. If it weren't, you wouldn't open it again tomorrow. If you don't open the app, then whatever will the advertisers do? Will someone please think of the advertisers!

We have created an existence where the screen is both the journey and the destination. The world has turned into this unfortunate brown-and-grey, messy thing the screen promises to defeat - or to keep our toes clean.

Except in one peculiar little corner of the App Store, where the architecture inverts.

There are 31 active GPS satellites in orbit around Earth. They were originally put up there by the U.S. Air Force in the 1970s and 1980s so that intercontinental missiles could be slightly more polite about where they landed; the civilian-grade signal was deliberately fuzzy until the Clinton administration switched off "Selective Availability" on May 2, 2000, at which point your phone could suddenly know which side of the street it was on. (Your phone, of course, did not yet exist. Patience was a virtue.)

A small group of mostly polite eccentrics has spent the twenty-five years since then quietly repurposing this multi-billion-dollar military infrastructure to send you on virtual scavenger hunts among fields of wildflowers and sunshine.

Geocaching is a worldwide game of GPS hide-and-seek with millions of physical containers tucked under benches and rocks in quiet, often beautiful and unseen spots on our planet. You reference a directory of latitude/longitude locations (in the year 2000, you'd plug latitudes and longitudes into an actual GPS device... now it's all built into a convenient phone app). Hike out to the location, dig around scorpion nests and damp leaves until you find the little container. Sometimes there are prizes. You sign a logbook with a tiny pencil, and you put it all back for the next geocacher. Try not to let the muggles see you.

Geocaching-inspired games like Pokémon GO, Pikmin Bloom, and Monster Hunter Now overlay creatures, gardens, and dragons onto your actual neighborhood, so that the bench you walk past every day is now also a virtual playground, or a virtual flowerbed, or in one specific case, a virtual rathalos.

(This overlay-virtual-stuff-on-the-real-world trick, in case you've been spared the term, is what the industry calls augmented reality, or AR).

There’s often a narrative backstory to motivate the game. Or just a story. ECHOES plays binaural audio as you cross a real bridge.

It gets weirder and more involved. Ingress pits you against other players in a global control of mysterious, mind-altering Exotic Matter leaking into our world through virtual portals. Zombies, Run! scares you as the undead chase you through your jogging workouts. Atlas Obscura's app catalogs 24,000 weird, but very real, places.

Tech isn’t always central to these experiences. The JR East stamp rally is a nationwide adult activity in Japan that requires you to schlep to a real train station, find a small physical inkpad on a real platform, and press a stamp into a small physical paper booklet. (It is exactly Pokémon GO except invented in the 1970s and run by the railway.) Reach International's scratch-off city cards are not technically software at all, but are functionally the same idea, on cardstock with QR codes. (The National Park passport book is the same idea on heavier cardstock with a slightly more patriotic font).

This is, as far as I can tell, the only category of consumer technology whose central premise is, in one form or another, please, for the love of God, get up off your couch.

A couple of Fridays ago, L and I drove out to Bash Bish Falls in Western Massachusetts, a destination we had picked, very deliberately, off one of the Reach International scratch-off cards. The cards are slightly ridiculous, entirely wonderful, and entirely physical: each card is a place, each scratched-off panel is a thing you actually do at a place and time. Bash Bish was ordered up, and so we were there, on a soft late-spring day where the woods are not yet hot and not yet biting, and you can briefly believe everything is going to be fine.

Halfway up the path, it occurred to me (partly because the trail runs right along the Massachusetts/New York border) that there was almost certainly a geocache somewhere along this stretch. I had not played in years, but it was exactly the kind of trail someone would have hidden one on. I pulled out my phone. There it was, on a small green pin: a cache deposited at the state line in 2008.

We hunted for it together. L found it: a fake log, hollowed out and nested inside a real log, intentionally placed at the seam where Massachusetts becomes New York. Inside: a small paper logbook, a handful of foreign coins, and a few traveled trinkets. We signed our names under the names of everyone who had been there before us. We took nothing. We put the log back inside the log, logged the geocache log on our phone, and put the fake log back inside the real log. Whew.

It occurred to me, walking back down the trail, that we had spent the entire day inside this genre without quite noticing. The Reach card had brought us to the place. The cache had rewarded the place once we were there. The world we already lived in held more than we had been noticing. And the GPS satellites flying overhead facilitated all of this.

By the time we got to the hotel, I had started downloading things. Ingress was on my phone by nightfall.

Two weeks later, the two square miles around my home transformed. The historic plaque at an otherwise anonymous street corner, the bus stop where everyone was staring at their phones, the worn mural on the side of Rudy’s, and every sidewalk crack I constantly trip over… all of it is renewed. It has become a contested geopolitical theatre.

There are virtual Ingress portals in parks and greenbelts, and the brutalist sculpture by the train. There are factions; there are alliances; there are people I have never met locally, whom I have nevertheless decided how I feel about based on what color flag they planted near my coffee shop.

I am not going to tell you my faction. We don't do that out loud. (Also: I have been Ingress-pilled for less than a month and am still working out what loyalty looks like in a game whose enemy team is mostly, statistically, my actual neighbors. There’s a metaphor buried here, I’m positive.)

This is, technically, a smartphone game. It is also not very much like a game.

It is more like a reason: a reason to take the long way, a reason to take the corner I normally don't, a reason to notice the mural by the bell tower because it is also a portal to hack, and noticing it for the first time is the loop. The stakes are modest, slightly silly, and involve a virtual blue triangle on a screen. They are also entirely sufficient to change a route to work. My journey veers off the daily path.

Three surfaces. One is software, one is paper, one is a fake log inside a real log on a state line. They are all doing the same job as an orienteering merit badge does for a kid moving through real terrain with a map and a compass (the same job, for that matter, this newsletter does for the week I just had).

They dignify the lived thing.

They say: this walk counted; mark it. And they give you a small synthetic reason to be where you already, on some level, wanted to be… in a body, in a place, on a Friday afternoon in May, on the line where Massachusetts becomes New York.

That, I think, is the load-bearing premise of the entire genre. Not augmented reality. Not gamification. A much smaller, much older thing dressed up in newer clothes.

A confession, two weeks in.

The two square miles around my home are also now a feed.

I have spent more of my precious decent-weather-for-Boston outdoor days looking at the small glowing rectangle in my hand than at the actual murals, statues, and corner-store awnings the rectangle keeps plotting at me. I have walked past real people in my neighborhood without seeing them, instead getting irrationally irritated by anonymous people with names like “Bluedog9134.”

I have, on at least one occasion that I am willing to admit to in print, almost walked directly into a street sign on Mass Ave because there was a resonator decaying on a portal half a block away and I needed to top it up, now, before the green team noticed.

My step count went up. My pace went down. The walk became a series of small stops at portals… hack, recharge, deploy, move on… at the speed not of a person enjoying a Tuesday, but of a person playing the slot machine they happen to be standing inside of.

Ingress promised to be a door pointing outward. In my actual usage, less than a month in, it has installed itself as a destination dressed up as a door. The mural is still a portal; the portal is still attached to the world, but my eyes are on the screen, not the world, and the screen knows it. It keeps pulling me inside. The neighborhood is the wallpaper. The game is the room.

I am, for the record, still playing. The trade (phone in hand for steps that would otherwise not happen) is, on net, the right one for me right now. But it is a trade, and the genre's story is that there isn't one. There is.

Which raises the question: what actually separates the apps that keep the genre's promise from the ones that quietly break it?

The phone has to leave your hand for the genre to keep its promise. The apps that earn a reputation and warm memories, as I formed them at Bash Bish, are the ones structured to push you outside and then get out of your way. The ones that pull your eyes back to the screen every thirty seconds, no matter how lovingly designed, are doing a different job.

They are social media feeds with extra steps. Literally.

The case for this is mostly in what survived. The genre split, after the 2016 Pokémon GO supernova, into roughly three buckets. There were the live-service giants that grafted location onto a regular collection game (Pokémon GO, Monster Hunter Now).

There were the high-commitment subcultural strategy worlds for the deeply (ahem) “dedicated,” of whom I guess I am now one (Ingress, Geocaching).

And there were the quiet ambient companions that did not really try to be games at all and instead just thickened the walk (ex. Pikmin Bloom, which is mechanically a pedometer with a houseplant subroutine, and ECHOES soundwalks, and Zombies, Run!)

What the best of these apps share is not the AR layer. Many of them have basically no AR layer. What they all share is that they hook into an already-existing walking routine and lay a small, dignifying, slightly playful structure on top of it. The screen, when there is a screen at all, is a door, not a destination.

Researchers in Human-Computer Interaction (the wing of computer science that bothers to care whether software is actually joyful for the humans using it) have started calling it "heads-up computing": the design stance that computation should support real-world activity rather than dominate the user's attention. The Communications of the ACM piece is unusually plainspoken: it frames the design goal as "freeing them from common constraints," meaning the user.

Meaning, in the end, the body.

What is interesting about heads-up computing as a phrase is that it suggests a direction the entire device industry is now slowly drifting in (and that the products which have been drifting that way for the last quarter-century, mostly without anyone naming it), are small, durable, slightly weird, and almost never on the front page of breathless tech reporting: The pilgrim app for the Shikoku 88 temples. Remote X, which is half urban theatre and half quiet GPS-voice critique. Strava Beacon, which is the deeply prosaic feature that lets one trusted person see where I am while I run. Or the genuinely strange anti-get-outside ones like Pokémon Sleep, which is, and I am not making this up, a Pokémon game you play by going to bed

Wildly different products for wildly different audiences. Structurally, the same: the screen as a door, then out of the way.

By that test… and it is the only honest one I know… most of the famous apps in this genre fail. Including, if I am being candid about my own pocket, the one I have been Ingress-pilled by for the last three weeks. The apps that pass tend to be the ones nobody made a movie about: a tupperware in the woods, a stamp on a paper booklet, a 1991 audio walk through a forest that isn't there anymore.

Last spring, the company that gave us Ingress and Pokémon GO did a strange and revealing thing. It sold the games business to Scopely, kept the maps, and renamed itself Niantic Spatial.

If you have ever wondered why anyone bothered building a free game in which you walk around catching imaginary creatures: this is your answer. The creatures were the carrier pigeon. The thing being carried, all along, was the map — a high-fidelity 3D model of essentially every interesting outdoor space on Earth, painstakingly trained by the actual feet of actual Pokémon Trainers. That map is now its own company, and it has a multi-year partnership with Snap, which has announced lightweight AR Specs.

The bait won the headlines. The map kept the promise.

The implication, if you squint, is that the next wave of this genre may not be "more walking games." It may be walking companions. A small, polite, spatial agent in the corner of your glasses that knows the neighborhood almost as well as you do, and occasionally suggests the long way home, and possibly also tries to sell you a coffee. That is either the future I want or a Black Mirror episode I am already three minutes late getting up to leave.

Or thereabouts. Letterboxing on Dartmoor predates the British Empire's high-water mark. The stamp-collection ritual at Japanese train stations — JR East stamp rallies and the smartphone app called EKITAG — is a nationwide adult activity that involves taking the train to a real station, finding a small physical stamp pad on a real platform, and pressing the stamp into a small physical paper booklet. There is no creature. There is no AR layer. There is no glowing portal.

There is a stamp.

This is the most culturally robust version of "place collection" on Earth, running on rubber and ink and doing so happily for the better part of a century. The technology, when it shows up at all, is the occasion. It is not the point.

If you only do one thing from this issue, do this one — and the instructions are literally three words long.

ECHOES is a free app that hosts thousands of GPS-triggered soundwalks all over the world. Headphones in. Pick a walk near you. Pocket the phone. Go.

It reminds me of a friend of mine, the sound artist Halsey Burgund, who has spent the better part of two decades building the participatory version of this. His open-source platform Roundware does what ECHOES does — geofenced binaural audio triggered by where you happen to be standing — except the audio at any given place is contributed by everyone who has walked through it before you. ECHOES is, structurally, Audible. Roundware is structurally Wikipedia. Walk into one of Halsey's installations and what plays in your ears is the layered voice of strangers, each leaving the next person a memory, a song, a small confession at the same set of coordinates. (If "GPS-triggered crowdsourced participatory binaural audio of collective public memory" sounds suspiciously like the most beautiful version of this entire genre, that is because it probably is.)

The whole tradition runs back to the earliest of Janet Cardiff's audio walks, Forest Walk (1991), her foundational audio walk, the work she has said changed her thinking about art. It predates the smartphone by more than a decade, and it is still the cleanest demonstration I know of what this entire genre is for. Cardiff records, on binaural microphones, a voice walking the same path you are now walking, narrating things she sees that aren't there anymore. The result is uncanny in the dictionary sense. The trees become both more and less yours.

For four years, Detour was the most beautifully made consumer product in this entire genre: high-production GPS-triggered city audio tours that treated the city itself as a stage set, narrated by people who actually knew it. It is also gone. The founder's own farewell post is unusually candid about why: this category is brutal, even for things that are better than they need to be.

The lesson is the unglamorous one. Quality alone does not save you in a genre that asks the user to physically go somewhere. The survivors — Geocaching, Ingress, the stamp rally, the tupperware in the woods — are not, by any reasonable account, the prettiest products. They are the ones with the most stubborn small communities of weirdos, and the lowest possible expectation of polish.

You can read this as cynical (the product market is broken) or as hopeful (taste is not enough; you also need a tribe). I keep going back and forth.

So, that's the dispatch from outside.

The question I'd love to leave you with:

Which apps in your pocket are actually doors, and which have quietly turned themselves into rooms?

The next time you catch yourself looking at the screen instead of the neighborhood, you'll have your answer.

— David

On repeat this week: Roam by The B-52's, 1989. 🎶 “Roam if you want to, roam around the world. Roam if you want to, without anything but the love we feel.”🎶

Reading: Theory of the Dérive by Guy Debord, 1958. "A technique of rapid passage through varied ambiances." Sixty-eight years later, this is still the best name I know for what an Ingress walk does to a Tuesday.

Building: Multiple blue fields, portals, and resonators in Ingress.