HydroCalc Plus vs Kapy
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
HydroCalc Plus
A professional tool for hydraulic engineers to calculate pressure losses in piping systems. It supports US and SI units, offers an extensive pipe material and fittings database, and includes inverse calculations for design optimization.
- Friction head loss calculation (Hazen-Williams)
- US and SI unit support
- Extensive pipe material library
- Fittings and valves database
- Inverse calculation mode
- Real-time results (velocity, losses)
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The COMPLETE version of HydroCalc, with what the free app doesn't have: the FITTINGS SELECTOR. Pick elbows, valves, tees and reducers piece by piece and the app computes minor losses for you — in the calculator, the inverse calculator and the system curve. No K-value tables, no transcription errors. ALL INCLUDED: pump power, system curve, pipe database and Darcy-Weisbach with real fluids come with the app. One purchase, no in-app purchases. Professional hydraulic engineering tool for calculating pressure losses in piping systems. Essential for engineers, plumbers, and contractors designing water distribution networks. Key Features: Calculate friction head losses using industry-standard Hazen-Williams equation Support for both US (ft, gpm, psi) and SI (m, lps, bar) units Extensive pipe material library with pre-defined roughness coefficients (C-factors) Complete fittings and valves database including elbows, tees, valves, contractions, and expansions Inverse calculations to determine optimal pipe diameter, flow rate, or length for target head loss Real-time results showing velocity, friction loss, minor losses, and total system head loss What Sets Plus Apart: Unlike basic calculators, HydroCalc Plus accounts for both major losses (pipe friction) and minor losses (fittings and valves). The app includes a comprehensive database of K-factors for various components, allowing accurate total system pressure loss calculations. Perfect For: Water supply system design Irrigation network planning HVAC piping calculations Fire protection systems Industrial fluid transport Educational purposes in hydraulic engineering Technical Capabilities: The app considers all critical factors affecting pressure loss: flow velocity, pipe diameter, internal roughness, pipe length, and fitting configurations. Materials include PVC, polyethylene, steel, cast iron, concrete, and more with accurate C-factors ranging from 120-150. Inverse Calculation Mode: Unique feature allowing backward calculations - determine required pipe size for allowable head loss, maximum flow capacity, or optimal pipe length for your system constraints. Simple, intuitive interface with instant results. No internet connection required. Professional-grade calculations in your pocket. Note: the advanced modules are available in English and Spanish.
Kapy
Build daily routines with gentle encouragement from a virtual capybara. Track habits with simple check-ins or goal-based measurements, and visualize progress with a unique quilt. Share habits with friends and family for mutual motivation.
- Gentle habit tracking with capybara encouragement
- Flexible habit scheduling (daily, specific days, weekly)
- Goal tracking by quantity (glasses, minutes, pages)
- Progress visualization through a 'quilt' feature
- Group habit sharing with up to 6 people
- Home and Lock Screen widgets
- Customizable color themes
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A little progress feels better with a capybara by your side. Meet Kapy, a cozy habit tracker that helps you build daily routines with gentle encouragement. Drink more water, read a few pages, make time to move, or wind down before bed. Start small, find your rhythm, and give yourself room to be human. Your capybara is here for the little wins, the fresh starts, and the days when showing up is enough. SMALL STEPS, ONE TAP AT A TIME Check off a habit with a tap, or track an amount like 8 glasses of water or 20 minutes of reading. As you move through your day, Kapy wakes up, gets cozy, and celebrates your progress with you. A MISSED DAY DOESN'T HAVE TO END YOUR STREAK Life happens. Miss a day and come back the next to keep your streak going. Build consistency with a little breathing room. YOUR ROUTINE, YOUR WAY • Schedule habits every day, on specific days, or a few times a week. • Choose simple check-ins or goals measured in glasses, minutes, pages, steps, and more. • Set reminders for a time that works for you. • Keep your day organized into morning, afternoon, and evening. • Get a matching 3D icon automatically from your habit's name. BETTER TOGETHER Make a little time for each other. Share a habit with your partner, friends, or family in a group of up to 6 people. Pick your own capybaras, see who has checked in, and build a shared streak. Invite them with a link. Together uses iCloud, with no separate Kapy account to create. WATCH YOUR PROGRESS BECOME A QUILT Each day adds a patch to your progress quilt, with warmer colors as you complete more habits. Look back at your streaks, perfect days, and progress for each habit, or share your quilt to celebrate how far you've come. A COZY CORNER THAT FEELS LIKE YOU Log habits from Home and Lock Screen widgets. Find your favorite look with Honey, Matcha, Lavender, Peach, Cloud, and Cocoa color themes, plus dark mode for quieter evenings. START FREE. GROW WITH KAPY PRO. Start with up to 3 habits, reminders, and unlimited Together habits for free. Kapy PRO unlocks unlimited habits and all color themes, with monthly, yearly, and lifetime purchase options. No ads. Your habits are stored in your iCloud. Pick one small habit. Your capybara is ready when you are. Terms of Use: https://me.dmansodev.com/kapy-terms Privacy Policy: https://me.dmansodev.com/kapy-privacy-policy
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Verdict
The clearest difference is price: Kapy at Free against HydroCalc Plus's $6.99. HydroCalc Plus's advantage is in-app purchases (none vs 3) and iOS requirement (15.1 vs 26.2). On rating, review sentiment, ratings volume and update cadence there is nothing between them.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
Kapy is free to download; HydroCalc Plus costs $6.99 up front. Kapy sells 3 in-app purchases, starting at $1.99 per month. HydroCalc Plus asks for nothing beyond the download.
On the App Store both sit at effectively the same score — 5.0 for HydroCalc Plus against 5.0 for Kapy. Both are backed by a comparable volume of ratings — 1 and 2 respectively. Written reviews split almost evenly too, at 100% and 100% positive.
HydroCalc Plus ships an update every 3 weeks, Kapy fortnightly. The most recent releases landed on November 1, 2026 and November 5, 2026 respectively.
| Parameter | HydroCalc Plus | Kapy |
|---|---|---|
| Price | $6.99 | Free — better |
| Rating | 5.0 (1 ratings) | 5.0 (2 ratings) |
| Positive reviews | 100.0% of reviews | 100.0% of reviews |
| Number of ratings | 1 | 2 — better |
| Update frequency | Every 3 weeks | Fortnightly — better |
| Ads | No | No |
| In-app purchases | No — better | Yes |
| Monetization | Paid | Freemium — better |
| Devices | iPhone, iPad, iPod — better | iPhone, iPad |
| Requires iOS | 15.1 — better | 26.2 |
| Further details — not scored | ||
| Size | 34 MB | 69 MB |
| Age rating | 4+ | 4+ |
| Developer | Transparent Blue Water LLC | David Manso |
Customer experience
HydroCalc Plus
Kapy
In-app purchases
HydroCalc Plus
No in-app purchases
Kapy
- Kapy PRO Monthly$1.991 Month
- Kapy PRO Yearly3 Days trial$6.991 Year
- Kapy PRO Lifetime$3.99








