Your tank, your device, your data

Log it. Chart it. Know when something's off.

Every entry is stored only on this device, nothing is uploaded anywhere. Enter a reading below and watch it plotted against safe reference ranges, in red the moment something drifts.

Log a Reading

Import from CSV or Excel

Already tracking readings in a spreadsheet? Bring your whole history in at once instead of retyping it.

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Your free month is up

You've been logging readings for 30 days, thanks for trying it out. Your existing data is safe and still visible below. Unlocking removes this screen for good, on this device, forever.

$9.99 once, for life

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Got an idea or found a bug?

This is v1. Tell us what's missing, what's confusing, or what broke, we read every message.

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