ATOM works with no signal. It keeps a copy of your whole tour on this device (the web and the iPhone app) and refreshes it in the background whenever you have signal: the calendar, every day for the next three weeks, hotels, travel, contacts, guest lists, advance, Who's On, and the money screens you're allowed to see.
WITH NO SIGNAL: a banner says "Offline. Showing your tour as of 2:14 PM." That time is when the copy you're looking at was last refreshed. The banner only comes on after a few seconds without signal, and stays a few seconds after signal is back, so a weak connection never makes it flicker. A slow answer is not offline: if the server takes more than 8 seconds, ATOM shows your saved copy so the screen isn't stuck, and only says Offline if the answer then fails or still hasn't come after 22 seconds. Open ATOM once with signal on a new phone or computer so it can download the tour.
FILES WITH NO SIGNAL: boarding passes and other files attached to a flight, and day files (tech packs, maps, anything attached to a day), are downloaded to the device for flights and days from yesterday to three days ahead, so they open at a gate or in a basement with no signal. Any flight or day file you open once is kept too. Kept files stay up to 14 days after you last opened them, up to about 200 MB per device; the Sync page shows how many are kept. Money receipts and personnel documents are not kept on the device.
SAVING OFFLINE: these saves wait on the device (they survive closing the app) and go when signal comes back: schedule changes, day notes, day schedule rows and set lists, hotels and rooms, new contacts and edits to people already in Contacts (someone added on two devices stays one person), expenses and their receipt photos, settlements, buyouts and per diem runs including in-person signatures (money only for whoever holds the tour's money key; a receipt photo uploads first, then the expense), guest list adds, edits, approvals, declines and removals (a removal waits for your pick if someone changed that guest meanwhile), VIP door check-ins (they keep the time you tapped; a fan already checked in on another device stays checked in), the advance checklist, ground transport already on the tour, and Who's On. The banner counts them: "3 changes waiting to sync." Anything else (other file uploads, reading documents, deleting money records) needs signal. In Money these always need signal, because they add or remove budget lines: Send to budget and Take off budget, posting or unposting a per diem run, voiding a run, any cash payout change (updating or deleting a posted one, cash received in hand). Offline they say there's no signal; try again once you have it. Money waits as one piece: if anyone changed the same settlement, buyout or per diem run meanwhile, the whole save waits for your pick, and an expense's amount, currency, date, card and category are picked together. Signatures are never lost to a pick: per diem signatures taken on two devices are combined. Quick Buyout checklists from two devices are combined too. A receipt snapped with no signal (Money > Expenses > Add Expense > Snap Receipt) can wait to be read: tap Read it when I have signal and the form closes with nothing saved. When signal is back ATOM uploads the photo and reads it (only with Smart Capture on), the banner says how many receipts are ready to add, and the Sync page lists each one with what it says (Receipts to add). Review and add opens Add Expense filled in from the receipt; it becomes an expense only when you tap Save Expense. Discard drops it. Or type the details yourself and save right away. Same rule as other offline money: only for whoever holds the tour's money key, and a receipt snapped on another artist's tour asks you to switch to that tour first. A hotel or venue typed offline is saved as typed; once it syncs, ATOM looks it up on Google and offers what it found on the Sync page (Use it fills in only what's still empty).
WHEN SIGNAL COMES BACK: ATOM checks each waiting change against the server first. Nobody else changed that field: it goes through. Someone changed the same thing meanwhile: it waits for you under Changed in two places: pick the winner on the Sync page (tap the banner). Both versions sit side by side with when each was changed and every detail that differs. Tap Keep mine or Keep theirs, or pick field by field. Nothing is overwritten without you choosing. Changes to different fields of the same day or person both stay, and the rest of that same save goes through right away; only the field that clashed waits for you.
COULDN'T SEND: if the server turns a change down (for example, your role can't edit that), it's listed with the reason, Try again and Discard. Discard puts your screen back to the server's version.
PRIVACY: passport scans and bank, wire and tax numbers are never kept on the device. Passport numbers and expiry dates are, so the passenger list and immigration pack work at a border with no signal. Signing out deletes the device copy, and if changes haven't synced yet ATOM asks before deleting them.
"ATOM STOPPED THIS SCREEN FROM SENDING THE SAME REQUEST OVER AND OVER": a screen got stuck asking the server for the exact same thing again and again (more than 60 times in 10 seconds). ATOM holds back just that one request for a minute so it can't flood the server, and lets ATOM's team know so they can fix the screen. Reload the page. Everything else keeps working, saves with different details still go through, and nothing you saved is lost.