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Stone Pass – Kidney Stones app

An app for people with kidney stones, and their healthcare providers, to support them to decide whether to wait for the stone to pass or to have surgery.

Stone Pass – Kidney Stones app	By Know Stone LLC
	Features Education and information.
Country of origin	USA
Clinical review	Read a clinical review below.
Security and privacy	Does the app: Collect medical information? Yes Require a login? No Have password protection? No Have a privacy policy? No Require internet access to use? Yes Read more about safety and security when using apps. Brochures: Tips to improve your privacy and security [PDF, 65 KB] Healthify He Puna Waiora, NZ Staying safe online(external link) Netsafe, NZ
Cost	Free
Advertisements	This app contains no ads.
How to get the app	(external link)

The Stone Pass app uses real-world observational data to guide kidney stone treatment decisions (passage or surgery). It aims to help you make decisions with your healthcare provider by providing statistical data on what happened with other people who had a kidney stone of similar shape, location, and pain intensity.

After you enter data on your kidney stone, such as size, location and pain scores, the app provides information on:

the number of people (out of 100) with similar stone size and location who tried to pass their stone vs how many chose surgical intervention
the number of people who were successful in passing their stone, and how many who tried to pass their but ended up requiring surgery.

The app uses real-world observational data to help guide kidney stone treatment decisions. The outcome data is presented as a statistical measure (out of 100) in a way that's easy to understand.

For the complete app description, go to the app App Store(external link) or, for a more detailed review, see Reviews.

PROS	CONS
✔ Very easy to use. ✔ The output display is very clear and easy to understand with a 100-point colour variable plot to demonstrate percentages of patients attempting to pass their stone and those needing surgery. ✔ There's an extra information section that provides useful information regarding position and size of stones, and a brief history of natural stone formation. ✔ Developed by a US-based urologist specialising in stone disease and referenced to guidelines and literature.	✘ You need to know your stone size and location (proximal, mid, distal). ✘ Medical jargon is used but there is an FAQ section to help you understand medical terminology. ✘ The results output screen displays a “Confidence Level” – low, medium, or high. It's not clear what this is in reference to. ✘ It would be good to include additional educational elements that address dietary advice, fluid intake, what to expect when passing a kidney stone, and what surgical intervention involves.

PROS

CONS

✔ Very easy to use.

✔ The output display is very clear and easy to understand with a 100-point colour variable plot to demonstrate percentages of patients attempting to pass their stone and those needing surgery.

✔ There's an extra information section that provides useful information regarding position and size of stones, and a brief history of natural stone formation.

✔ Developed by a US-based urologist specialising in stone disease and referenced to guidelines and literature.

✘ You need to know your stone size and location (proximal, mid, distal).

✘ Medical jargon is used but there is an FAQ section to help you understand medical terminology.

✘ The results output screen displays a “Confidence Level” – low, medium, or high. It's not clear what this is in reference to.

✘ It would be good to include additional educational elements that address dietary advice, fluid intake, what to expect when passing a kidney stone, and what surgical intervention involves.

Clinical review

Reviewer: Johanna Lim, Clinical Pharmacist (Cardiology Expert) & Pharmacist Prescriber. Health NZ Te Whatu Ora Te Matau a Māui Hawke’s Bay
Date of review: July 2025
Platform: Apple
Version: 1.1
Comments: Overall, the Stone Pass app is easy to use in the decision-making process of patients with kidney stones, particularly giving you the likelihood that you can pass your stone and not require surgery. However, to utilise the app, you must know the size and location of your kidney stone.
The output data is based on real-world data which provides valuable insight for you and your healthcare provider. Results are colour-coded and very easy to understand.
Educational content provided in the FAQ section helps you understand how kidney stones form, but it would be useful to include more educational content such as dietary advice.
Safety concerns: This app may create or drive some assumptions with the results it provides, however it includes a disclaimer that the app does not provide medical advice. The app also assumes that patients have already been in contact with a medical professional.
New Zealand relevance: Yes
Concerns: Relatively safe app when used in conjunction with medical advice from a healthcare professional.
The information in this app should not replace medical advice.
Although relevant to New Zealand users, it would be useful to include some brief information about what passing a kidney stone may feel like, and what surgical intervention involves.

Kidney stones
Kidney health topics
Consumer guide – how to choose a health app
Clinicians guide – how to choose a health app
New Zealand-based apps
NZ Health App Library

Disclaimer: The NZ Health App Library is a free consumer service to help you decide whether a health app would be suitable for you. Our review process is independent. We have no relationship with the app developers or companies and no responsibility for the service they provide. This means that if you have an issue with one of the apps we have reviewed, you will need to contact the app developer or company directly.