Comparison

Stream vs OpenPPG

Price, ratings, monetisation and update history for both apps, side by side โ€” with what reviewers say about each.

Head to head
About

Stream

Features
Read full description

Stream helps you keep track of important information over time. Never forget a detail again! Log a note for yourself anytime, and an automatic timestamp is stored alongside it. Automatic summaries give you insight in the trends that matter most to you, like finance, health, or personal productivity. Some example uses: - tracking credit card purchases - logging medication usage - weight watching - measuring your exercise over time Plus, it's 100% offline so the data never leaves your phone! You don't have to trust a third party to protect your data.

About

OpenPPG

Features
Read full description

OpenPPG is a free, research-oriented iOS application designed to close the gap in accessible and transparent PPG data acquisition. Built by researchers for researchers, it enables recording of raw, high-quality photoplethysmography (PPG) signals directly from the smartphone camera, with full export for scientific analysis. Key Features โ€ข Raw signal access โ€“ capture unprocessed PPG waveforms with complete control over export (CSV format). โ€ข Flexible preprocessing โ€“ raw signals, basic and advanced filtering, signal quality assessment or fully calculated metrics in one app to enhance your research โ€ข Feature extraction โ€“ access directly over 11 automatically calculated temporal and morphological metrics without need for advanced signal processing โ€ข Metadata & annotations โ€“ mark events while taking measurements in real time and customise forms to fit your study protocol โ€ข Explainable pipeline โ€“ reproducible acquisition process with transparent documentation to ensure research reliability. Why OpenPPG? Most mobile tools restrict access to raw data, hide acquisition details, or require payment. OpenPPG removes these barriers by providing a free, standardised, and reproducible way to acquire PPG signals. It supports innovation in signal processing, machine learning, and digital biomarker discovery. Important: OpenPPG is intended solely for research purposes. It is not a medical device and must not be used for diagnosis, treatment, or patient self-monitoring.

Screenshots

Stream3 screens
OpenPPG4 screens

Verdict

The call

The clearest difference is iOS requirement: Stream at 15.0 against OpenPPG's 17.6. On price, ads, in-app purchases and device support there is nothing between them.

Scored on Price ยท Rating ยท Positive reviews ยท Number of ratings ยท Update frequency ยท Ads ยท In-app purchases ยท Monetization ยท Best chart rank ยท Devices ยท Requires iOS

CostPrice ยท In-app purchases ยท Ads ยท Monetization

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

Scorecard1 real difference ยท 5 level
Stream versus OpenPPG: the parameters behind the verdict, then further details
ParameterStreamOpenPPG
PriceFreeFree
Update frequencyโ€”Monthly
AdsNoNo
In-app purchasesNoNo
DevicesiPhone, iPod โ€” betteriPhone
Requires iOS15.0 โ€” better17.6
Further details โ€” not scored
Size16 MB9 MB
Age rating4+4+
DeveloperRex Garlandresearch app

In-app purchases

None

Stream

No in-app purchases

None

OpenPPG

No in-app purchases

Questions

Is Stream free?
Stream is free to download, with no in-app purchases.
Is OpenPPG free?
OpenPPG is free to download, with no in-app purchases.
Do Stream or OpenPPG have ads?
Neither Stream nor OpenPPG shows ads.

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