Apple Health and mood tracking: what is possible today

Apple Health includes a feature called "State of Mind." It is a real, well-designed daily mood logging surface. It is also not a complete bipolar tracker, and it is worth being clear about what each one does.

What State of Mind does

Apple Health's State of Mind asks two questions: how you feel right now (a momentary mood) and how you've felt overall today (a daily mood). The scale is a slider with descriptive anchors from "very unpleasant" to "very pleasant," paired with optional emotion words.

It logs to your Apple Health database, where other data (sleep, exercise, heart rate) lives. You can see week, month, and 6-month views.

What it does well

Privacy. Apple Health data is encrypted on-device, and (per Apple) end-to-end encrypted in iCloud sync when you have two-factor authentication on and a passcode set on the device. The data lives with you.
One-tap entry. The interface is fast.
Sits next to other health data. Sleep, activity, and mood in the same place.
Built into iOS. No extra app to install or remember.

What it misses (especially for bipolar)

Single mood axis. "Pleasantness" collapses depression, elevation, irritability, and anxiety into one number. The bipolar use case requires those as separate scales.
No medication tracking. Apple Health has medications as a feature, but State of Mind does not connect mood entries to specific doses or adherence patterns.
No clinical-style anchors. The slider is descriptive, not anchored to clinical scales.
Limited charting. The pattern view is OK for general well-being. It is not designed for spotting prodromes or comparing this month to baseline.
No way to share with a clinician. Apple Health does not produce a clinician-facing summary.

What this means in practice

For someone with bipolar disorder, State of Mind is useful but not sufficient. The most common pattern that works:

Use State of Mind for the daily "how was today, overall" check-in — a low-friction back-up log
Use a bipolar-aware tracker for the four-axis scales, sleep-with-mood charting, and visit prep

The two are not in conflict. They answer different questions.

Sleep is the high-leverage overlap

Apple Health is good at sleep tracking, especially with an Apple Watch. For bipolar disorder, sleep is one of the most reliable early-warning signals2008. If you're already tracking sleep there, you can read the nightly hours and type the same number into MoodSync alongside your mood scales.

Privacy comparison

Apple's App Store privacy framework requires every developer to declare what data their app collects2024. Apple Health data is end-to-end encrypted in iCloud (with two-factor authentication and a device passcode set, per Apple's published condition). MoodSync mood values stay on your device with optional private iCloud sync. The two apps land on similar Apple-stack privacy postures, with different feature scopes.

The pragmatic recommendation

If you have an iPhone and bipolar disorder:

Use Apple Health for sleep tracking (especially if you have a Watch)
Use a bipolar-first tracker for the mood scales, meds, and visit prep
Do not try to make Apple Health the whole picture — it is not designed to be

A few caveats

This is not a review of every Apple Health feature. State of Mind is the relevant one for mood tracking. Other Apple Health features — medications, cycle, exercise — can be useful inputs to your overall picture without replacing a dedicated mood tracker.