Features

Track what matters to you

Define the variables you want to record. Each one has a name, an optional note, and a type:

Boolean — a yes / no toggle. Good for habits, events, or symptoms that are present or absent.
Number — a slider with a configurable range and decimal precision. Good for ratings, measurements, and quantities.

Record in seconds

Each day starts fresh. Update a slider or flip a toggle and your change is saved immediately — there's nothing to submit. Swipe between days, or tap the days bar at the top of the screen to jump to any specific date.

Daily notes Improved in 2.7

Add a free-form note to any day for context that doesn't fit a variable. Long-press the note pencil to insert the current time and build a timestamped log through the day. Tap the note to open a clean read-only view.

Search New in 2.5

Ask questions like "days I slept under 6 hours and skipped the gym" or "days where the note mentions 'headache.'" Combine criteria with AND or OR, save queries you'll come back to, and view results as a list of cards or a heat-map calendar.

Reports Improved in 2.8

Build a custom PDF from your variables and saved searches. Pick the time range, arrange your graph cards, and export to share with a doctor, coach, or your future self. Each card can use its own custom time window — measured in days, weeks, or months — so a long-running heat map can sit next to short-range trend plots in the same document. Reports save and sync, so you can regenerate the same layout whenever you want.

Plot and compare Improved in 2.8

Long-press a variable to enter selection mode, then tap others to add them. Plot one variable as a heat map, or two or more as a line graph. Pan the plot's window around with a swipe of your finger, or pick a specific duration and end date from the controls above the chart.

Sync

Keep your data in step across devices, or back it up safely off your phone:

iCloud — sync through your private iCloud account. No setup required.
WebDAV — sync to any WebDAV server you control.

Private by design

Correlate has no servers, no analytics, and no telemetry. Your data is yours — stored on your device and (if you choose) on the iCloud or WebDAV account you control. See the Privacy Policy.

Lock with Face ID New in 2.8

Gate the app behind Face ID or your device passcode. There's no grace period: even a quick app switch will lock it again, and the lock screen covers any sheet that was open so the app-switcher snapshot never reveals your data.

Historical edit protection New in 2.8

It's easy to leave the app on yesterday's screen and accidentally change an old value. With historical edit protection on, edits to any day before today need a quick confirmation — Change This Once or Allow 5 Minutes for a backfill session.

Fast to open

Correlate is built to start instantly. Record a value and get back to your day — the app is ready before your thumb reaches the screen.