Apple Health AI Apps That Actually Respect Your Privacy: On-Device vs Cloud Comparison (2026)
Every health AI app on the App Store says it respects your privacy. But some send your heart rate and sleep data to cloud servers for processing, while others keep everything on your iPhone. Here is exactly which apps do what, and why the gap matters more than you think.
Quick answer: on-device vs cloud health AI
On-device health AI apps (Health Export AI Pro Chat, Risi.ai, Suvi, Sifa, Metrya) process your Apple Health data entirely on your iPhone. Your heart rate, sleep stages, HRV, and every other metric stay local.
Cloud health AI apps (ChatGPT Health, AI Health Export, Vora) send your health data to external servers. A summary of your metrics is transmitted to OpenAI, Google Gemini, or the app's own backend.
This guide breaks down every major app in each category, what happens to your data, and why one app uniquely bridges your data to other AI agents via MCP.
The 2026 landscape: why this matters now
Two things changed in 2026. First, ChatGPT Health launched in July. AppleInsider and TUAW confirmed the feature sends health metric summaries to OpenAI's cloud servers.
Second, a crop of on-device health AI apps arrived. Risi.ai went into beta with Apple's MLX framework. Metrya launched with a BYOK model. Suvi and Sifa use on-device AI for pattern detection. And Health Export AI (MetricBridge) added Pro Chat: an on-device AI chat with no cloud dependency, plus the only MCP bridge that feeds your data to Claude Desktop, Cursor, ChatGPT, and any MCP-aware agent.
The key question for any buyer: does the AI process your data on the phone, or does it leave the phone?
What "on-device" actually means
Three tiers exist when an app claims to be "on-device":
- Fully on-device. Everything runs on your iPhone. No network call for AI. Examples: Risi.ai (MLX), Suvi (Foundation Models), Health Export AI Pro Chat (on-device LLM).
- On-device preprocessing + cloud AI. Health data is processed locally, then an anonymized summary is sent to an AI API. Examples: Metrya (BYOK), Health AI Insight (BYOK). Your data reaches a third-party AI provider but not the app developer.
- Cloud AI. Raw or lightly processed metrics are sent to the app's backend or an AI provider. Examples: ChatGPT Health, AI Health Export (Gemini), Vora.
If an app sends health-derived data to a third-party server, it is not fully private regardless of the marketing language.
On-device health AI apps compared
Here are the main apps that process Apple Health data on your iPhone as of August 2026.
| App | AI processing | Data leaves phone? | MCP bridge | Price |
|---|---|---|---|---|
| Health Export AI | On-device LLM (Pro Chat) | No | Yes | Free + Pro trial |
| Risi.ai | On-device MLX | No | No | Free (beta) |
| Suvi | On-device Foundation Models | No | No | Free |
| Sifa | On-device Foundation Models | No | No | Free + $4.99/mo Premium |
| Metrya | On-device preprocessing + BYOK | Summary | No | Free + $14.99 lifetime |
| Health AI Insight | On-device preprocessing + BYOK | Summary | No | Free + Premium |
Health Export AI is the only app on this list that gives you both an on-device AI chat and an MCP bridge. The other on-device apps are data silos: you can ask an AI about your health inside the app, but you cannot pipe that data to your coding agent, writing assistant, or analysis tool.
Cloud health AI apps compared
These apps send your Apple Health data to external servers for AI processing.
| App | AI provider | What leaves your phone | MCP bridge | Price |
|---|---|---|---|---|
| ChatGPT Health | OpenAI | Health metric summaries | No | Free tier (limited) |
| AI Health Export | Google Gemini | Health data for cloud chat | No | Free + in-app purchases |
| Vora | Proprietary cloud AI | Health metrics + behavior data | No | Free + $12.99/mo Pro |
ChatGPT Health made waves in July 2026 by offering Apple Health chat inside the ChatGPT app. The trade-off: your health data travels to OpenAI's servers. For users who want a health AI that never transmits their metrics anywhere, this is a non-starter.
The missing link: MCP bridges
Every on-device app solves one problem well: answering health questions on your phone privately. But none let you export that data to AI agents for deeper analysis or custom workflows.
Health Export AI is the exception. It ships an open-source, zero-dependency MCP server (health-export-mcp on GitHub, 84kB on npm) with 14 read-only tools:
get_health_metrics: pull raw values for any of 190 metrics across a date rangeget_trends: week-over-week or month-over-month trend mathcompare_periods: A/B two time windowsget_structured_export: tidy JSON bundle for deeper analysisquery_health_data: flexible plain-language queries across metrics
With that server running, you can ask Claude Desktop "How did my recovery trend this week compared to last week?" and it calls the tools live against your local data. No CSV, no upload, no stale snapshot. You can ask Cursor to write a script correlating your HRV with sleep stages.
None of the other on-device apps offer this. Risi, Suvi, Sifa, and Metrya are closed boxes: they read your data, they talk to you, but they never give your data to your other agents.
How to choose the right app
Your choice depends on what you need:
- You just want private health Q&A on your phone. Risi.ai, Suvi, Sifa, and Metrya all handle this. Pick based on design and price. None have an MCP bridge.
- You want private health Q&A plus data export to AI agents. Health Export AI is the only option. Pro Chat gives you on-device AI chat with provenance cards. The MCP server gives Claude, Cursor, ChatGPT, and any agent live, read-only access to your health history.
- You trust cloud AI with your health data and want zero setup. ChatGPT Health or AI Health Export work out of the box. Your data leaves your phone, but setup friction is near zero.
Our position. We built Health Export AI because we wanted both: an on-device health AI that answers questions privately, and an MCP bridge for our coding and analysis agents. No other app does both.
Frequently asked questions
What is the difference between on-device and cloud health AI apps?
On-device health AI apps process your Apple Health data entirely on your iPhone. Cloud health AI apps send a summary or raw data to a remote server (OpenAI, Google Gemini, or their own backend) for processing.
Which health AI apps actually keep Apple Health data on-device in 2026?
The main on-device health AI apps are: Health Export AI (MetricBridge Pro Chat), Risi.ai (MLX-based, beta), Suvi (Apple Foundation Models), Sifa (on-device pattern detection), and Metrya (BYOK mode). ChatGPT Health and AI Health Export (Gemini) are cloud-based.
Does ChatGPT Health keep my Apple Health data private?
No. ChatGPT Health sends your Apple Health data to OpenAI's servers for AI processing (AppleInsider, TUAW July 2026). On-device health AI processes everything on your iPhone instead.
What does an on-device health AI app do that a cloud app cannot?
It processes your health metrics locally on your iPhone. Your data never travels over the internet. Health Export AI is the only on-device health AI app that also exports data to AI agents via an MCP bridge, giving you both privacy and agent access.
Can on-device health AI apps export data to Claude or ChatGPT?
Most cannot. Risi, Suvi, Sifa, and Metrya keep your data in their own app. Health Export AI is the only on-device health app with an MCP server for Claude Desktop, Cursor, ChatGPT, Windsurf, opencode, and any MCP-compatible agent.
Get private health AI plus an MCP bridge in one app
On-device AI chat with provenance cards. Zero-dependency MCP server for Claude, Cursor, ChatGPT, and any agent. 190 metrics, fully local. Free 7-day trial of Pro Chat. No account, no cloud.