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 | |