A team of four is standing in a mall basement in front of the right mural. They've taken the photo. The screen is spinning. One of them taps the button again. Another says "it's crashed" and starts looking for the app to delete, except there is no app, so now they're confused as well as stuck. Two floors up, the organiser's dashboard shows them as idle for eleven minutes.
Nothing crashed. The photo is sitting on the phone waiting for one bar of signal. When they walk to the escalator it will go through and they'll carry on. But nobody told them that, and the clues were printed before anyone asked the question.
The question usually arrives late: "We're running a hunt in the centre. Reception is patchy. Do players need internet the whole time?" Not the whole time. At three moments: when they open the game, when they move to the next task, and when they submit an answer. In between, the screen they already loaded stays put.
Here is the honest version of what you're running. PlayTours is a scavenger hunt that lives in the phone's browser. You build it in a web editor as chapters and tasks, players scan a QR code to join, and one person watches a dashboard. Because it's a web page rather than an installed app, the first load needs a connection, and so does every submit. There is no such thing as an offline scavenger hunt on anyone's platform; there are only hunts designed so the moments that need signal happen where signal exists. What you can change is which tasks you use where. It's free for up to 25 phones at once, with a watermark; pricing and IT details are in their own posts.
What fails first
Location tasks. These ask the phone where it is and complete when the player is within a set distance of a pin. Basements, granite streets, and dense crowds all give bad positions. Players get "not close enough" while standing on the right doorstep.
Anything live. The leaderboard and the team-location map on the dashboard update as data arrives. With no signal, they don't. People can still play without watching their rank; you just won't see them move on the map until they surface.
Automatic photo checking. When a team submits a photo, PlayTours checks it against your instruction and awards points. That check happens after upload, so with no upload there's no verdict. On the phone it looks frozen when it's simply waiting.
The first join. The QR scan has to load the game. Put your join point at the door, in the lobby, or anywhere with wifi. Not in the underground car park.
What holds up if you plan for it
Codes. A QR sticker or a short typed code on the task. Tape them where people already pause: the ticket desk, a museum caption, a café counter. Scanning is a local camera action; the submit still needs a moment of data, so place codes a few metres from known-good signal. We reach for codes whenever GPS is unreliable.
Check-off tasks. "Read this plaque, discuss it, mark as completed." The team taps one button. It still needs to submit, but it's tiny, so it goes through on a weak bar where a photo wouldn't.
Photos you judge yourself. Instead of automatic checking, photos can queue for a person to approve later from the dashboard. Players submit when they have signal, and you approve when you have a chair.
Puzzles on the screen. Word searches, multiple choice, scrambled phrases, combination locks. The solving happens on the device; only the answer needs a connection. Solve it in a tunnel, and it sends when you come out.
A layout that survives a basement
Chapter one, in the lobby or at the park edge, done in order: join, safety, and one easy multiple-choice so every team confirms they can submit. Chapter two, outdoors or in the gallery: a mix of codes and photos. Chapter three, back in coverage: the automatically checked photo or the shared gallery shot, so you get the good pictures when the connection is working.
Make teams complete chapters in order for this pattern. Free roam in a dead zone is how two teams end up in a service corridor.
Then paste this into the chapter-one briefing, word for word if you like:
"You don't need perfect internet the whole time. You do need a signal to open the game, load the next task, and submit. If a photo hangs, walk toward the entrance or the square and wait ten seconds. There's nothing to delete or reinstall. It's a web page, not an app."
Those last two sentences prevent the team in the first paragraph.
Test on the network your guests will use
Walk the route on cellular, not office wifi, and submit a photo from the worst corner. If it never returns, that corner becomes a code or gets dropped. And when people are underground, the dashboard will look quiet. That isn't a crash either.
Downtown steel in the US, a European old town, a Singapore mall basement, a Malaysian convention centre: same physics. If the event genuinely has to stay in a basement, make staff check-ins a check-off task plus a printed code at a manned table. That works, and it's honest.
Send hello@playtours.app the floor plan with the dead zones marked and I'll tell you which task types to keep.
-Mo
If you're building this in PlayTours
Task types by editor name: location and direction ("mark as arrived") tasks; QR/barcode tasks and access codes; no-answer tasks for check-offs; judged-image for photos a person approves, judged-image-ai for automatic checking; word-search, multiple-choice, scrambled-phrase, and combination-lock for on-screen puzzles. Turn on "complete challenges in order," and put the Instant Join QR at the entrance. Related: alternatives to GPS check-ins.