Systematic Evaluation of Smartphone Applications for the Medical Management of Nephrolithiasis

Abstract

Objective:

The aim of this study was to comprehensively evaluate the quality of patient-oriented, mobile health applications (apps) available for medical management of kidney stone disease (KSD).

Materials and Methods:

A systematic search was performed to identify apps from the Apple and Google Play app stores. Eligible apps were divided into two categories: (1) fluid apps and (2) dietary apps. Descriptive characteristics were summarized and app quality was independently evaluated on the basis of technical quality, usability, clinical value, and privacy/security. The validated Mobile App Rating Scale (MARS) was the backbone for the evaluation framework.

Results:

In total, 31 apps (18 fluid apps and 13 dietary apps) were included. Fluid apps outscore dietary apps in all dimensions of MARS quality. All but one fluid app exceeded the minimums acceptable MARS score of 3.0 vs 46% of dietary management apps. Dietary apps feature less functionality and most are limited to noninteractive informational content. While most data-capturing apps provide a privacy policy and ensure that security measures are taken to protect user identity, only 36% offer users choice or consent for secondary use of their data after data have already been collected. Overall, only one app has undergone any form of real-world clinical investigation.

Conclusions:

Fluid management apps outperform dietary apps in technical quality, usability, and clinical value at the cost of greater privacy/security risks. Despite not being targeted to patients with KSD, they are higher in most quality measures and offer greater functionality to support long-term disease management compared with dietary apps.

Introduction

The exponential growth and advancement of mobile technology have facilitated a global marketplace of mobile device applications (apps). Whereas these digital tools have increasingly subsumed all routine aspects of life, this trend has been particularly evident in health care with proliferation of mobile health (mHealth) apps providing disease-specific support and tools for managing overall wellness. As of 2018, there were more than 318,000 mHealth apps available across a variety of mobile platforms, nearly twice as many from 2015.¹ It is estimated that nearly a quarter of mHealth apps are concentrated on chronic disease management, reflecting the growing importance of taking an active role in one's personal health.¹

Kidney stone disease (KSD) is one of the most common medical conditions, affecting ∼1 in 11 people in the United States.² For many individuals, recurrence is common.³ Based on underlying risk factors, including coexisting medical conditions, this risk can be dramatically higher, subjecting patients to the costs and comorbidity of repeat surgical interventions, painful stone events, and the negative influence on health-related quality of life. The key to breaking this cycle of recurrence lies in preventive management strategies: intensive dietary counseling, lifestyle modification, and/or medication therapy tailored to an individual's risks.

The latency of nephrolithiasis and intermission between symptomatic stone events are among the many factors that beget poor adherence to treatment and lifestyle recommendations. As with other chronic conditions, preventive strategies to reduce the risk of progression and recurrence rely on the maintenance of appropriate self-management behaviors. mHealth apps possess great potential to support long-term disease self-management,⁴ but the number of commercially available options can be overwhelming. Additionally, standardized methods to evaluate app quality are lacking. We sought to comprehensively evaluate patient-oriented mHealth apps available for the medical management of KSD.

Materials and Methods

Search criteria and app selection

The search, screening, selection, and assessment of apps were performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols (PRISMA-P) framework.⁵ Smartphone apps related to medical management of kidney stones were then identified by searching the Apple and Google Play app stores using 13 search terms (Supplementary Data S1). Searches were performed in April 2020. This study did not require institutional review board approval.

Apps were deemed eligible for further screening if all of the following criteria were met: (1) the potential to support the medical management of stone disease based on app name or description, (2) intended for use by patients/consumers, and (3) available in English. Apps providing access to didactic articles, designed for use by medical providers, requiring an external device, or targeting the nonmedical management of stones (including surgical and medical expulsive therapy) were excluded. Based on their primary intended functions, all remaining apps were then divided into two categories for further screening and selection: (1) fluid management apps or (2) dietary management apps. Within each of these subgroups, the top 10 most highly rated apps were included in the study. This was repeated for both app stores. Although the number of ratings is in constant flux, our team adopted this approach as it is most representative of the user experience.⁶

Descriptive assessment

All apps meeting the inclusion criteria were downloaded onto an iPhone 8 Plus (iOS, version 13.3.1) or a Moto G5 Plus (Android OS, version 8.1.0). Descriptive metadata were extracted from the app store overview provided by the developer and by use of the relevant app.

App evaluation framework

We drew on principles of the Johns Hopkins Digital Health Scorecard⁷ and previously reported criteria⁸ to define four core domains of app quality: (1) technical quality, (2) usability, (3) clinical value, and (4) privacy/security (Table 1). We then employed a combination of previously reported mHealth rating tools^9–11 along with other pertinent collected data to construct a comprehensive framework for app content analysis and quality evaluation that fulfilled these domains.

Table 1.

Core Domains of Mobile Health Application Quality and the Instruments by Which They Were Evaluated

Domain	Description	Criteria	Instruments
Technical quality	Proper functioning of the app and professionalism of design	Performance speed, quality of graphics, visual appeal, and interoperability	MARS (esthetic and functionalitya dimensions)
Usability	Evaluation of user experience	Ease of use, instructions on use, consistency of gestural design, and navigation ease	MARS (functionalitya dimension)
Clinical value	How well available functions support health-related goals of the target user (clinical utility), evidence supporting app use in clinical practice (clinical efficacy), and all elements of app cost	Specific functions of the app, customization, interactivity, features that promote repeated use, quality, and quantity of informational content, credibility of the developer, real-world evidence base, costs related to app purchase, and overall health care	MARS (engagement, information, and subjective quality dimensions)
			IMS Institute for Healthcare Informatics functionality criteria
Privacy/security	Criteria related to data protection mechanisms and transparency of data capture/use practices	Privacy policy, data encryption mechanisms, user consent to data capture and secondary use of data, and user access to data after collection (e.g., rectification)	Federal Trade Commission's recommendations on Fair Information Practices in the Electronic Marketplace

^a The MARS functionality dimension does not categorize or evaluate the clinical utility of built-in functions. Rather, the term “functionality” within this instrument refers to ease of use, app performance speed, logic of flow when navigating between screens, and overall consistency of gestural design.

app = application; MARS = Mobile Application Rating Scale.

The backbone of our evaluation framework was the Mobile App Rating Scale (MARS),¹² which objectively rates app quality on 19 items across 4 dimensions (engagement, functionality, esthetics, and information quality). Accordingly, it fulfills three of our four core domains of app quality—all, but privacy/security. A four-item subjective quality assessment is included in the tool as well. All items are scored using a five-point Likert scale (Supplementary Data S2). Assessments were performed by four independent reviewers. All reviewers viewed the MARS training video and tested each app for at least 10 minutes before scoring to ensure consistency. Mean scores with standard deviations were calculated for each of the four dimensions and the overall (objective) score and the subjective quality score.

The IMS Institute for Healthcare Informatics functionality score was used to further evaluate the clinical value of the included apps (Supplementary Data S3).¹³ This tool consists of 11 functionality criteria, with 1 point given for the presence each function (scored 0–11). In contrast to the MARS, the IMS functionality score focuses solely on the availability of various functions in support of health management goals, as opposed to the relative quality of functions present. In this way, it provides an added level of granularity.

The final core domain, privacy/security, was also evaluated for each app, including the presence of a medical disclaimer and data capture practices. If data were captured, we determined whether they met the criteria of personal identifiable information (PII)—that is, any information that would permit an individual to be directly or indirectly identified or to be physically or electronically contacted.¹⁴ If PII was collected, we further evaluated the privacy protection measures taken by the app developer based on the recommendation from the Federal Trade Commission (FTC)'s policy on Fair Information Practices in the Electronic Marketplace.^15,16

Descriptive statistics were performed using SPSS, version 22.0 (SPSS, Inc., Chicago, IL).

Results

Our search strategy yielded 31 kidney stone medical management apps that met our final inclusion criteria (18 fluid apps and 13 dietary apps). The flow chart in Figure 1 provides a detailed overview of the screening process.

FIG. 1.

PRISMA diagram illustrating the search methodology for included apps. apps = applications; PRISMA = Preferred Reporting Items for Systematic Reviews and Meta-Analyses. Color images are available online.

Descriptive characteristics

Table 2 summarizes the included apps and their characteristics. All but one fluid management app (WaterMinder^®) charge for initial download and the vast majority (15/18) offer in-app purchases or require a monthly payment following a short free trial period. Four dietary apps require initial purchase. Upgradeable features across all apps include access to more detailed dietary content information, more advanced fluid tracking features, and removal of advertisements. Overall, 2 of the 31 apps (7%) report medical expert involvement in their development.

Table 2.

Descriptive Characteristics of Included Applications

App name	Developer	App store	Key function	Unique added feature(s)	Apple App Store			Google Play App Store				In-app purchases	Ads	Medical expert involvement	Apple health connectivity
					Average star rating	Number of ratings	Initial download price	Average star rating	Number of ratings	Downloads	Initial download price
Fluid management apps
Drink Water Reminder N Tracker	Phoenix Healthcare	Both	Fluid intake tracker		4.5	85,429	Free	3.6	210	>10K	Free	Yes	Yes—both	No	Yes
Plant Nanny 2	Fourdesire	Both	Fluid intake tracker	Gamification; overhydration warning for excessive fluid intake	4.7	26,281	Free	4.6	49,553	>1M	Free	Yes	Yes—both	No	Yes
Drink Water * Daily Reminder	App Rover	Both	Fluid intake tracker		4.6	16,026	Free	4.2	21,272	>1M	Free	Yes	Yes—Google Play	No	Yes
Water Reminder—Daily Tracker	VGFIT LLC	Both	Fluid intake tracker	Actual hydration adjustment based on fluid type (e.g., 0.9 for coffee)	4.7	15,599	Free	4.4	1154	>50K	Free	Yes	Yes—Google Play	No	Yes
WaterMinder®	Funn Media, LLC	Both	Fluid intake tracker	Customizable phrase shortcuts to voice assistant (e.g., Siri) to log intake and check daily goal status; actual hydration adjustment based on fluid type (e.g., 0.9 for coffee)	4.8	14,960	4.99	4.3	1874	>100K	Free	Yes	Yes—Google Play	No	Yes
Drink Water Reminder, Tracker	Energy Flow	Apple	Fluid intake tracker	Daily intake goal adjustable based on physical activity level	4.7	14,952	Free	n/a	n/a	n/a	n/a	Yes	Yes	No	No
My Water & Drink Reminder	Victor Sharov	Both	Fluid intake tracker		4.7	10,660	Free	4.2	5562	>100K	Free	Yes	Yes—Google Play	No	Yes
Daily Water Tracker Reminder	Grassapper LLC	Both	Fluid intake tracker		4.7	6106	Free	4.4	5800	>100K	Free	Yes	Yes—Google Play	No	No
Drink water	TOH Co., Ltd.	Apple	Fluid intake tracker		4.6	5679	Free	n/a	n/a	n/a	n/a	No	Yes	No	Yes
My Water—Daily Water Tracker	Harmonybit Ltd.	Apple	Fluid intake tracker		4.7	4388	Free	n/a	n/a	n/a	n/a	Yes	Yes	No	Yes
Drink Water Aquarium	Andreas Budde	Both	Fluid intake tracker		4.7	2405	Free	4.6	20,404	>500K	Free	Yes	Yes—both	No	No
Aqualert	AqualertApp	Both	Fluid intake tracker		4.6	633	Free	4.6	74,194	>1M	Free	Yes	Yes—Google Play	No	Yes
Water Drink Reminder	Leap Fitness	Google Play	Fluid intake tracker		n/a	n/a	n/a	4.8	569,357	>10 M	Free	Yes	Yes	No	No
Water Time	Mobile Creatures	Google Play	Fluid intake tracker	Gamification; actual hydration adjustment based on fluid type (e.g., 0.9 for coffee)	n/a	n/a	n/a	4.6	139,678	>5M	Free	Yes	Yes	No	No
Water Reminder—Remind Drink Water	olympic.game.studio@gmail.com	Google Play	Fluid intake tracker		n/a	n/a	n/a	4.8	134,013	>5M	Free	No	Yes	No	No
Drink Water Reminder & Water Tracker	Codium App Ideas	Google Play	Fluid intake tracker	Data export feature; team feature to compete with others	n/a	n/a	n/a	4.6	106,708	>1M	Free	Yes	Yes	No	No
BeWet	Beforest Apps	Google Play	Fluid intake tracker	Daily intake goal adjustable based on physical activity level	n/a	n/a	n/a	4.8	20,307	>1M	Free	Yes	Yes	No	No
Drink Water Reminder: hydration app	Easy Health Group	Google Play	Fluid intake tracker		n/a	n/a	n/a	4.7	18,463	>1M	Free	No	Yes	No	No
Dietary management apps
Oxalator	Max Odnovolyk	Apple	Oxalate content glossary		2.8	19	Free	n/a	n/a	n/a	Free	No	No	No	No
Oox	Baliza GmbH	Apple	Oxalate content glossary	Education: hyperoxaluria and low-oxalate diet advice	4.6	95	Free	n/a	n/a	n/a	Free	Yes	No	No	No
Oxalater	Yoctopia LLC	Apple	Dietary oxalate tracker	Oxalate content glossary	4.0	4	$7.99	n/a	n/a	n/a	$7.99	No	No	No	No
OxiPur	conneqtA, Inc.	Apple	Oxalate content glossary	Education: low-oxalate diet advice	4.0	2	Free	n/a	n/a	n/a	$6.99	No	No	No	No
Kidney Stones (Oxalate)	CTNT	Both	Oxalate content glossary	Education: kidney stone basics and general dietary recommendations	1.0	5	$3.99	1.0	2	>100	$3.49	No	No	Yes	No
Stone MD	Nariman Gadzhiev	Both	Dietary and fluid intake tracker	Urine pH diary; stone recurrence risk calculator	4.0	145	Free	4.0	133	>5K	Free	No	No	Yes	No
Kidney Disease 101	Wenquiang Yan	Apple	Education: fluid and dietary recommendations for prevention		3.7	3	$2.99	n/a	n/a	n/a	$2.99	No	No	No	No
Oxalate Food Counts (Kidney Stones)	Denise Anderson	Google Play	Oxalate content glossary		n/a	n/a	Free	4.7	47	>1K	Free	No	No	No	No
Kidney Stone Symptoms & Treatment	Fall in Love Studio	Google Play	Education: stone symptoms, causes, treatments, and prevention		n/a	n/a	Free	0.0	0	>1K	Free	No	Yes	No	No
Stone Diet Kidney Gallbladder	SendGroupSMS.com	Google Play	Education: prevention advice		n/a	n/a	Free	4.8	25	>5K	Free	Yes	Yes	No	No
Kidney Stone Removal Remedies	StatesApps	Google Play	Education: naturopathic treatment for stones		n/a	n/a	Free	4.2	21	>5K	Free	No	Yes	No	No
Reduce Stones	Shakeel	Google Play	Education: prevention advice	Fluid intake tracker	n/a	n/a	Free	5.0	13	>100K	Free	No	No	No	No
Repair Your Kidneys Naturally	Koodalappz	Google Play	Education: symptoms and treatments for stones (including naturopathic treatments)		n/a	n/a	Free	4.3	396	>5K	Free	No	Yes	No	No

MARS evaluation

Table 3 presents individual results of the MARS analysis for the included apps. The average MARS scores are 3.62 for fluid apps and 2.98 for dietary apps. Only one fluid app has a mean MARS score below 3.0 (indicating acceptable quality), compared with 7 of the 13 (54%) dietary management apps. With regard to item #19 of the MARS instrument (“Evidence base: has the app been trialed/tested?”), only 1 of the 31 apps (Stone MD) has undergone clinical investigation with evidence available in the scientific literature.¹⁶

Table 3.

Mean Comprehensive Mobile App Rating Scale Scores and Rankings by App Category

Fluid management apps				Dietary management apps
Ranking	App name	Mean MARS scorea	Mean subjective score	Ranking	App name	Mean MARS scorea	Mean subjective score
1	WaterMinder	4.78	4.67	1	Stone MD	3.80	3.77
2	Water Reminder—Daily Tracker	4.40	4.20	2	oxaBrow	3.73	2.90
3	Plant Nanny 2	4.22	4.00	3	OxiPur	3.52	2.87
4	Drink Water Reminder, Tracker	4.19	4.10	4	Reduce Stones	3.48	2.30
5	BeWet	3.96	3.50	5	Kidney Stone Symptoms & Treatment	3.30	2.00
6	Drink Water Reminder & Water Tracker	3.80	3.25	6	Kidney Stones (CTNT)	3.18	2.40
7	Water Time	3.75	3.25	7	Oxalate Food Counts	2.95	2.20
8	Drink Water * Daily Reminder	3.76	3.27	8	Stone Diet Kidney Gallbladder	2.85	1.30
9	My Water—Daily Water Tracker	3.68	3.03	9	Oxalater	2.75	1.90
10	Water Reminder—Remind Drink Water	3.49	2.75	10	Kidney Disease 101	2.63	1.75
11	Drink water	3.43	2.97	11	Oxalator	2.38	1.60
12	Drink Water Reminder: hydration app	3.34	2.25	12	Kidney Stones Removal Remedies	2.30	1.30
13	Drink Water Reminder N Trackers	3.33	3.03	13	Repair Your Kidneys Naturally	1.85	1.00
14	My Water & Drink Reminder	3.25	2.87
15	Drink Water Aquarium	3.21	2.87
16	Aqualert	3.09	2.43
17	Water Drink Reminder	3.06	2.75
18	Daily Water Tracker Reminder	2.42	1.63

^a Mean MARS score reflects the mean score of the four objective dimensions (engagement, functionality, esthetics, and information). This reflects items 1 to 19 of the instrument.

The MARS score breakdown for the top 5 and the lowest scoring apps is displayed in Figure 2. The highest scoring fluid management apps outscore those for dietary management, reflected in the greater areas bounded by their respective pentagons. These differences are most evident in the engagement (how interesting and interactive the app is), functionality (how usable the app is in the hands of a user), and subjective dimensions. The top 5 fluid apps are fairly comparable across all quality dimensions, with the exception of the top-ranked app (WaterMinder) outperforming the others in quality and quantity of information within the app. While the top dietary apps do not differ much in the functionality and esthetic dimensions, there is far greater variability in the other aspects of MARS quality.

FIG. 2.

Radar charts of the top 5 and worst scoring apps for (a) fluid management and (b) dietary management of kidney stone disease according to MARS. Pentagons were created with each corner representing a different domain of MARS, each presented on a scale of 1 to 5. Larger areas represent higher overall quality scores. MARS = Mobile App Rating Scale. Color images are available online.

Functionality

Fluid management apps outperform dietary apps in total functionality (Fig. 3). Of a maximum score of 11, the mean IMS scores are 6.6 and 2.5, respectively. All 18 fluid apps are fluid intake trackers that collect and display user-entered data, set target intake goals, and provide drink reminders. Functionally, the apps are differentiated by the presence of added features such as customizable fluid goals, multiple methods of displaying data, and integration with existing social media platforms, among others.

FIG. 3.

Radar chart showing the percentage of apps per group that fulfilled each of the 11 functionality criteria of the IMS Institute for Health Informatics functionality score. Color images are available online.

Among dietary apps, Stone MD is the most comprehensive app providing four unique functions: dietary (oxalate and purine) intake tracker, fluid intake tracker, urine pH, and calculated stone recurrence risk. Nine apps (69%) provide educational content; this is the sole function of five of these apps. Five apps (38%) provide an oxalate content glossary, of which one allows users to track their oxalate intake (Oxalater).

Data privacy and security

In total, 23 apps (74%) capture any user data, including all 18 fluid apps and 5 dietary apps. A privacy policy is provided by 21 of these apps. Eleven apps (35% overall; 48% of data-collecting apps) collect PII. While many apps inform users of secondary use of their data, including third-party data sharing practices, only 36% (4/11) of those collecting PII provide users with choice/consent for such practices after data have already been collected (Supplementary Table S1).

Discussion

This is the first study to systematically analyze mobile device apps targeted toward patients for medical management of KSD. In the absence of a standardized strategy for evaluating mHealth apps, we used a set of evaluation tools to assess apps based on technical quality, usability, clinical value, and privacy/security. Our analysis demonstrated that available fluid management apps offer greater functionality to support long-term disease management compared with dietary apps despite not being targeted to patients with KSD. However, they are limited to fluid intake tracking and their reliance on user-entered data imposes a burden on users and introduces privacy risks. Dietary apps are more limited in functionality, many serving as informational tools alone.

As a group, fluid management apps are largely interchangeable fluid intake trackers that lack specificity to any disease process. Still, they possess great potential to positively affect self-management strategies in KSD. Adequate fluid intake is unequivocally recognized as an important measure in both empiric and targeted stone prevention approaches.^17,18 Higher quality apps differentiate themselves through gamification features, more personalized customization, and connectivity to centralized health tracking applications (e.g., Apple Health app), which may reinforce continued user engagement.

By contrast, dietary management apps are targeted to nephrolithiasis, but outscored with respect to technical quality, usability, and clinical value. The majority of the functions provided by these apps can be viewed as those of convenience rather than necessity—most notably, noninteractive, text-only patient education materials, and oxalate content glossaries. There is little evidence that informational tools alone are sufficient to support self-management in chronic conditions.¹⁹ Furthermore, the relatively limited number of functions observed across the group is generally isolated to separate apps with minimal intelligent design or integration. Where sustained adherence to behavioral modifications and prescribed treatments is the cornerstone of kidney stone prevention, integrative tools and multimodal management strategies are greatly needed. It is worth noting that only two apps provide some degree of combined fluid and dietary management functionality. However, the fluid intake tracking by these apps is inferior to that of the 18 fluid management-exclusive apps.

To date, only one app has been clinically investigated in any capacity. In a user satisfaction study of 49 patients who used the app for 1 day, Becker and colleagues reported that 72% of participants believed the Stone MD app was more useful for preventing stone relapse than traditional educational materials. Fifty-seven percent expressed interest in continuing use of the app.²⁰ By convention, medical interventions must undergo rigorous and iterative investigation to demonstrate safety and clinical efficacy before widespread adoption. Unfortunately, the fast pace of commercial app development and upgrades limits the ability to perform quality outcomes research.²¹ With regard to KSD, these limitations are further compounded by the intermission between stone events and inevitable user fatigue with manual data entry, both of which favor faltering adherence to such digital tools.

Finally, the capture of data that fuel higher-level functionality and personalization exposes users to potential data privacy risks that are inadequately addressed by many existing apps. Failure to provide a privacy policy should be an initial red flag to a user or prescribing provider. Such statements are important as they detail data collection practices, security measures to protect user identity, rights of the developer and user, and the opt-in nature of consent to data collection with download and use of the app. Encouragingly, more than 90% of the stone management apps that capture data provide a privacy policy. These findings are in contradistinction to just 45% of pelvic floor muscle training apps in a recent review,²² highlighting the variability of data privacy practices in mHealth.

We acknowledge that there are several limitations to this study. First, there is no standardized means of evaluating mHealth apps. As such, we relied on our institution's guidelines on mHealth app development⁷ and the corpus of prior mHealth investigations to tailor a comprehensive and reproducible evaluation strategy for apps supporting the medical management of KSD. At the base of this framework was the validated MARS.¹² We provided additional analysis of clinical value and privacy/security features that should be integral to decisions on the use of such digital tools. Second, all reviewers were under the age of 40 years and comfortable with mobile technology. There is likely to be a wide range of fluency and competence with mHealth apps among potential users and this introduces potential bias. Third, we excluded apps focused on the surgical management of stones, which may have included medical management functionality. Finally, our searches were limited to the largest, most popular application stores, Google Play and the Apple App Store, discounting other less popular marketplaces. As of 2019, there were 2.57 million and 1.84 million available apps in the Google and Apple stores, respectively. By comparison, the Windows Store and Amazon Appstore accounted for just 1.16 million apps combined.²³

Despite these limitations, we believe our study offers a number of important implications. The search strategy cast a wide net to capture and review all patient-oriented apps supporting medical management of KSD—the results of which serve as a valuable reference for clinicians and patients alike. As a corollary, this study helps draw attention to future opportunities for impactful mHealth innovation in this disease space.

For clinicians interested in incorporating digital health tools into their current stone practice, and for patients able to incorporate these tools into disease self-management, mHealth apps hold great potential to support medical management strategies for long-term prevention. We recognize that many aspects of overall health maintenance are challenging to dissociate from self-management strategies for KSD. This includes ensuring adequate water intake, prioritizing weight management, and limiting dietary salt intake, among others. With this in mind, perhaps our kidney stone patients are best served by relying on more disease-agnostic apps such as water intake trackers and others that leverage the more immediate outcome measures of other disease states (i.e., diabetes and hypertension) to support adherence to parallel, stone-related, medical management strategies. Further work should focus on thorough evaluation of clinical value—notably, clinical efficacy.

Conclusions

Fluid management apps are higher in quality and offer greater functionality to support long-term disease management compared with dietary apps despite not being targeted to patients with KSD. Based on these findings, clinicians may tailor mHealth recommendations to interested patients to aid in long-term management of nephrolithiasis.

Abbreviations Used

app

mobile device application

FTC

Federal Trade Commission

KSD

kidney stone disease

MARS

Mobile Application Rating Scale

mHealth

mobile health

PII

personal identifiable information

PRISMA-P

Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols

Author Disclosure Statement

Dr. B.R.M. reports personal fees received as a consultant for Boston Scientific Corporation (Marlborough, MA) unrelated to this study. All other authors have no conflicts of interest to report.

Funding Information

No funding was received.