What works when a web app goes offline?
A page opens in airplane mode. Good. Now try the task you need it for. Can you check a box, save the result, close the app, and find it again? “Works offline” needs a more specific answer than “the screen loads.”
Check four different kinds of work
| Task | What has to be available |
|---|---|
| Read a guide | The page, images, and navigation must be cached. |
| Calculate an estimate | The calculator code and required rates must be on the device. |
| Save a checklist | The app must save entries locally and report failures. |
| Send an order | A server connection, or an explicitly designed queue with later confirmation. |
A saved draft is not a delivered order. The screen should distinguish them. Never tell a customer a message was sent just because it disappeared from an entry box.
Prepare while you still have reception
Open the app online and complete whatever download it requires. A service worker can arrange cached files for later use, but the app decides which files to save. An unseen page may be absent unless it was deliberately included.
This knowledge base attempts to save its guides, search data, and worksheets as one release. Wait for its offline-ready status, then test the pages you need. External source websites are not included.
Run a realistic check
Use a test entry rather than customer work. Disconnect from the network, open a different guide or job, make a correction, and reopen the app. Then reconnect and check whether anything needs sending.
Repeat on the devices staff actually use. A desktop network simulation is useful, but it does not prove that a phone will preserve records through the same conditions.
Plan for an incomplete download
Give staff a fallback before they go somewhere with no signal. That may be a printed guide or an exported list. If an app only shows a blank screen offline, report the exact page and device to its maintainer.
Cached information can be old. For a staff guide, show the revision date and who owns it. Do not let an old downloaded procedure silently pass as the current one.
Sources & verification
Documentation checked October 25, 2026. Platform instructions are documented guidance; physical-device behavior has not been verified for this article.
Your choice stays on this device. It is not sent to the site owner.