Field operations
Salesforce Field Service mobile offline: what works, what waits
What the Salesforce Field Service mobile app does offline, what waits for signal, how priming decides what the phone holds, and how to test it.
On September 16, 2026, the Salesforce Field Service mobile app dropped support for iOS 18, and Android 14 followed on October 4, according to Salesforce’s technical requirements page. It is a good moment to check how the app behaves offline. The short answer: the Field Service mobile app works offline for the appointments, work orders and records the phone loaded before the technician lost signal. Edits and new records queue on the device and sync later. A handful of features, such as service report PDFs and the inventory tab, need a live connection.
What works offline in the Field Service mobile app
Salesforce says plainly that the app “can work effectively when offline”, on one condition: the phone must sync while it still has a connection. That first sync is called priming. It copies the technician’s schedule and the records attached to it onto the device.
Once primed, a technician can open assigned service appointments and work orders, read the details, update fields, add records and run mobile flows against what is cached. Anything created offline is stored on the phone and sent to Salesforce when the device reconnects. Salesforce notes that a record created offline does not display fully until that sync happens, so a technician may see a new record looking incomplete until then.
Offline search works too, with a catch from Salesforce’s offline considerations: it needs a briefcase set up by your admin, and the records must have turned up in an earlier search while online. A customer the technician has never looked up will not appear.
What waits until the phone reconnects
Salesforce’s mobile app limitations page lists the gaps. These are the ones dispatchers and technicians notice first.
| Task | What happens with no signal |
|---|---|
| Saving changes in a mobile flow | The flow runs on cached data; its creates, updates and deletes wait for a connection, unless your org has LDS enabled for those users |
| Service report PDF | Generated only online; the request can be queued, and a preview may show older data |
| Related lists on briefcase records | Not available offline |
| Time sheets on briefcase records, and the inventory tab | Not available offline |
| Technician location | Not sent; the last known location goes when the phone reconnects |
| Records never primed or opened | Not visible from other records, including new ones |
| Default field values | Not applied offline |
None of this is unusual for offline software. It does mean the office should not promise a customer a signed service report on site if that site has no coverage, and any process that depends on a mobile flow saving immediately needs another look.
Priming decides what the phone holds
Priming starts by loading every service appointment in the technician’s default list view, Salesforce explains in its performance guidance for the app. The bigger that view, the longer priming takes. A related setting, Past Days and Future Days in the date picker in Field Service Mobile settings, defaults to 45 days each, and Salesforce says trimming it speeds up offline syncing and load times.
Salesforce suggests a custom list view for offline work that excludes closed appointments and limits scheduled start and end to about seven days on either side. A few published limits also shape the design: the app fetches at most 1,000 service appointments across all list views, related lists show up to 50 records, and priming follows relationships only two levels deep, so a field three lookups away will be empty offline.
Two habits matter in the field. Salesforce says to “always prime to completion before going offline”, so technicians should open the app on shop Wi-Fi and let it finish before leaving. On iPhones, the device stays awake during priming only when Low Power Mode is off.
Timestamps and other sync surprises
The surprise that reaches the office is time. By default, a record saved offline is stamped with the time it synced, not the time the technician did the work, and the NOW() function returns sync time as well. A technician who finishes a job at 10 in the morning on a farm with no coverage and reconnects in town at 3 shows a 3 o’clock completion. Salesforce Field Service Support can enable a setting called Accurate Record Dates for Offline to fix this. We would ask for it before rollout whenever billing, labor or service agreements depend on completion times. Without it, Salesforce suggests copying LastModifiedDate into a separate date and time field on the service appointment.
Two smaller issues come from the same page. If a phone’s clock runs ahead, sync can fail with “CreatedDate in future” errors, and new records created in a flow do not get their auto number until they sync, so a technician cannot quote a work order number to the customer from the driveway.
Phones and coverage for long rural routes
The app needs a Field Service Mobile user license and Enterprise, Unlimited or Developer Edition, per Salesforce’s requirements page. That page also sets hardware tiers. The minimum tier for Android lists 5 GB of RAM and 5 GB of free storage, though the same page’s key points say Android devices need 8 GB or more of RAM, and devices with 4 GB or less are not supported. For iPhones the minimum is iPhone 14 or iPhone 12 Pro and later. Salesforce recommends the higher tier, with 15 GB free, for anyone loading 20,000 or more records offline, and says the 5 GB minimum is not enough for high volume briefcases.
For remote work it suggests dual SIM or carrier aggregation, and notes that satellite service can support background syncing where there is no cellular signal. Where a service territory spans several rural counties, that advice is worth costing before you buy a fleet of phones. Our guide to field service scheduling software for HVAC covers the scheduling side of the same decision, and the grower CRM guide has a similar offline test for sales reps.
Test it on your worst route first
Before the whole crew depends on it, take one technician, one real phone and the longest route you run. Prime on shop Wi-Fi, then work a full day: complete jobs, add notes and photos, run your mobile flows and try to open a customer nobody looked up that morning. Back in coverage, check four things in Salesforce: every change arrived, the completion times are right, no sync errors came back, and the office saw what it needed when it needed it.