If you're an engineer and interested in building a little application then read on! CommonHealth is a (free, non profit) app that patients can use to download their health data from their health care providers. We're all about open interoperability with the ability to for developers to build on top of the app using the SDK to ingest the data of a patient and build any visualizations/analytics etc.
There's zero backend data aggregation, all data lives ONLY on your personal device once you download it from your health provider, and all data is thus deleted if you simply uninstall the app.
So that's to say, if you're in the US market and want to build your own functionality, you definitely have that opportunity, as we've done the work connecting to 1000s of providers (with 100k+ coming by end of year)
Reach out if you want to get started here