Mood, Sleep & Symptom Tracker

Log mood, sleep, energy and five more daily signals in seconds. Meridian keeps your entries on-device and shows associations across your history—not causes.

See your days in context.

Meridian is a private daily journal for noticing patterns across mood, sleep and everyday body signals. A quick check-in builds a calendar you can look back on, while on-device analysis compares your own entries over time.

LOG EIGHT DAILY SIGNALS

Record mood, sleep, energy, focus, stress, headache, digestion and exercise in one calm check-in. The fixed set keeps each day consistent, so your history remains easy to compare. Optional reminders can help you remember when you choose to log.

LOOK BACK WITHOUT GUESSING

Use the calendar and history to revisit individual days and see how each signal changed. Trend views turn separate entries into a clearer timeline while keeping the underlying values visible.

NOTICE ASSOCIATIONS

Meridian aligns signals by calendar day and uses an exploratory statistical screen based on permutations before highlighting a relationship. For example, it may show that lower energy often appears after shorter sleep in your own entries. An association is not proof that one signal caused another, and Meridian does not present it as one. When the data is limited, the app says so.

MERIDIAN PRO

Pro unlocks the full association network, next-day estimates checked on held-out earlier entries when your history is sufficient, 60- and 90-calendar-day trend ranges, and export to a real JSON file. Estimates stay hidden unless they outperform a simple baseline in those historical checks. You decide where an exported file goes.

PRIVATE BY DESIGN

Your daily health entries and their analysis stay on your device. Meridian uses RevenueCat for purchase validation, entitlements and aggregate purchase analytics. That purchase history is not linked to your identity or used to track you. Your journal entries, health signals and on-device analysis are never sent to RevenueCat.

Meridian is designed for personal reflection. It does not diagnose conditions, provide treatment guidance or replace professional medical advice.

Made by Studio AM for iPhone and iPad.