Can Underbark work on Apple Watch without your iPhone nearby?

Yes, with important limits

Underbark calculates scores on iPhone. A compact score summary can reach the Underbark Watch app.

Before leaving your phone behind, separate two questions: can you open the app, and is the information you want current? An available screen is not proof that everything has refreshed. Read any date, update message, or missing-information label alongside the number. If you cannot establish which day it describes, leave that uncertainty in place rather than treating an older display as a new reading.

Check before you leave

Open Underbark on your iPhone and look at the day you intend to review. Check whether the information you expected is present, rather than checking only whether the app opens. Then look at the display you plan to use while you are away. This gives you a point of comparison if something later looks different, incomplete, or unchanged. It is a practical check, not a guarantee that a later update will arrive.

If an update time is shown, distinguish it from the period the information describes. A receipt time answers when an update arrived; a day label answers which day you are viewing. Neither is a reason to fill in a gap yourself. Read the surrounding wording before comparing two numbers.

When information is older or unavailable

Treat an older result as context for its stated day. It may still help you understand what you saw earlier, but it should not stand in for information from a later period. An unchanged number alone cannot tell you whether a refresh succeeded or whether a newly available result happens to be the same.

A missing result is a different situation from a low result. Do not turn an empty screen into a zero, or assume that a missing night means nothing was recorded. Start with the message shown and the period you expected to see.

For incomplete nights, the guide to missing Apple Watch sleep data explains what to check without inventing the missing detail.

Connection is only part of the question

Apple distinguishes between features that use a connection and features that remain available without one. The options depend on the model and connection available. A Wi-Fi or cellular indicator is useful connection information, but it is not confirmation that a particular app has received everything it needs. Avoid using another app's ability to open as a test of whether this one has refreshed.

Apple's guide to using Apple Watch without an iPhone nearby covers the device-level options. Those options are not a promise that every third-party feature works independently.

When your phone is available again

Open Underbark on iPhone, follow any relevant instruction on the other screen, and check the displayed day again. If information is still absent, keep the gap visible. Repeatedly looking at the same number does not establish that a new update arrived. Note the wording you see and whether the expected information is also absent on the phone; that distinction is more useful when asking for help than guessing at a connection failure.

Use Underbark support for help with an unclear display. For permission choices, see Underbark data controls.