Your Health Records as Plain Markdown: Owning Files You Can Still Open in Ten Years
A health app is a temporary custodian of a permanent record. You will change phones, and probably operating systems. You may stop paying, or the company may stop existing. The one part of this you can actually control is whether your history is stored in a file you can still open when the app is gone.
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Quick answer
Plain text is the format that survives. A Markdown, JSON or CSV file carries its own meaning: the column names, the dates, the values and the units are all in the file, so any text editor can open it and any person or program can read it without the app that wrote it. A proprietary database cannot do that, because it needs its product to interpret the rows. The ten-year test is simple: export once, close the app, and open the file. If you can read your own history without the product, you own it. If you cannot, you are renting access to it.
What you are really buying when you pick a health app
You are not buying a chart. You are buying a place for your history to live, and that place has a format. Three futures are worth thinking through, because each one has already happened to someone:
- The app is discontinued. The servers go dark on a date you find out about by email, if you get an email at all. If your history only existed in their database, the export window is the whole product now.
- The app is sold. New owners, new terms, a new retention policy. Your record moves as part of the acquisition.
- The app changes its model. A feature folds into a tier, a metric gets dropped, a destination disappears. Your data is fine. Your access to it is not.
None of those requires malice. They are ordinary outcomes for software. The defence is not loyalty to a better company. It is a file that does not depend on the company at all.
Why plain text wins on time, not on features
Plain text is not the most capable format. It cannot hold a schema constraint or a foreign key. What it has is a property no database has: the reading cost stays near zero for decades. A text file needs a machine with an editor. No licence, no version pin, no account, no network. A proprietary export needs the vendor's importer, a supported OS and a version that still understands the file. Every one of those is a dependency that can expire.
That is why the format argument is an ownership argument. A file you can read is a file you can move, back up, diff, search and hand to a new tool. A file that needs an app is a file the app controls. The same rows, in two formats, are two different degrees of ownership.
What "plain" looks like in practice
Markdown gets the idea right: text that reads as prose to a person and as structure to a parser. A daily note can carry a heading, a short table of steps and sleep, and a line of context. It is readable on a phone, in a terminal, in a git diff, in any editor shipped in the last thirty years.
JSON and CSV are the same family with different strengths. CSV is a table: one row per reading, columns for type, date, value and unit, openable in any spreadsheet. JSON keeps nesting and metadata: a device name, a source priority, a grouping by day. Both are text, both are greppable. Both outlive the product that produced them.
MetricBridge exports JSON or CSV, your pick, to a destination you choose: iCloud Drive, a local folder, a machine on your LAN, or a webhook. There is no destination on by default, background export keeps the file current, and optional passphrase encryption covers the copy. What matters is not the extension, it is whether the meaning lives in the file. A closed binary that one app can open does not pass.
The honest limits of plain text
Plain text is not free of responsibility. It is readable by anyone who can open the folder, so where you put it matters more than the format. Encryption, a drive you control and a backup you have actually restored once keep the convenience from becoming a liability. It is also not a medical record in the legal sense. It is your copy of your own readings.
That is where the format pays off twice. A plain text export is the input to everything after it: a spreadsheet, a script, a local AI, an MCP client. Because the file is text, an agent can read it without a connector. Our own server does this: 22 tools, 20 read-only, zero dependencies, no outbound network calls in the read path. It reads the file. It does not phone home about it.
How to start the archive this week
- Export once now. The best time to own a copy is before you need it.
- Put it somewhere you control. A folder you back up, or a drive you own. Not a link that expires.
- Open it with the app closed. Read three rows out loud. If you cannot, find an app whose export you can read.
- Repeat on a schedule. A record is current only if the copy is.
Your health history is the longest-running dataset you own. It deserves a format that does not need a company to stay alive.
FAQ
What does plain text health data actually mean?
It means the file itself carries the meaning. A JSON, CSV or Markdown file opens in any text editor, with no app, no account and no vendor in the loop. A proprietary database needs the product that wrote it, and that product may not exist in ten years.
Does MetricBridge export Markdown?
MetricBridge exports JSON and CSV, both plain text. Markdown is the same family of file: human readable text you own. The important property is not the extension, it is that the meaning lives in the file rather than in an app database.
How do I check that a health app's export is really portable?
Export once, then open the file in a text editor with the app closed. If you can read the dates, metric names and values without the product, the export is portable. If you need the app to interpret it, or the file is a proprietary binary, it is not.
Is a plain text file safe for health data?
A text file is as safe as the place you put it. It is readable by anyone who can open the folder, so keep it on a drive you control and use encryption when the destination warrants it. MetricBridge offers optional passphrase encryption and leaves every destination off by default.
Own the file, not just the app
Export your Apple Health history as plain JSON or CSV to a folder you choose. Ask questions about it on your iPhone. Point your own agents at it over MCP. No account, no server of ours in the path.
Where it goes: answers are computed on the iPhone and your health data never reaches us or a cloud AI; exports go only to the destination you pick. What you get: all 194 metrics, on-device Ask with a provenance card on every answer, the Weekly Brief, and the Mac and Apple Watch apps. Price: $24.99 one time after a 7-day free trial, not a subscription. Wellness, not medical advice.
Written by MetricBridge. We build a private, on-device health AI for iPhone that also exports your Apple Health data to your own tools. About us · Privacy · Support