How Deep Is It? vs Hydrant Flow Test Calculator
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
How Deep Is It?
Explore physics concepts hands-on with this app. It uses your device's accelerometer to demonstrate falling body equations, allowing you to visualize and hear the distance traveled. Experience classic physics principles in an interactive way.
- Illustrates falling body equations
- Uses device accelerometer
- Large text distance display
- Audio feedback for distance
- Ad-free experience
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Physics AND fun! This app helps illustrate one of the most common falling body equations with your very own accelerometer-enabled device. Experience for yourself, in a hands-on way, how far your device has traveled using the classic physics equation: d = ½gt² Features: • See the distance with large text display • Hear the distance with audio feedback • Still ad-free as always!
Hydrant Flow Test Calculator
This tool simplifies hydrant flow testing by calculating total GPM from pitot pressures. It allows for outlet settings, flow extrapolation with a Supply vs Demand curve, and plotting demand points for PASS/FAIL results. Save test data with location and project details for future reference.
- Calculate total GPM from pitot pressures
- Configure outlet diameter and hydrant coefficients
- Extrapolate flow with Supply vs Demand curve
- Plot demand points for PASS/FAIL analysis
- Save test results with date, time, and project info
- Log hydrant locations via GPS
- Review saved test history
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Hydrant Flow Test Calculator is a field-friendly calculation and reporting tool for fire protection professionals, engineers, inspectors, contractors, and AHJs who need to evaluate and document hydrant flow test results. The app helps calculate hydrant flow from field readings, compare available water supply against system demand, estimate downstream friction loss, and export professional PDF reports. Key features: • Calculate hydrant flow using static pressure, residual pressure, pitot pressure, outlet diameter, and discharge coefficients • Calculate total test flow and flow at a target residual pressure • Compare available supply against system or pump demand • Review demand pass/fail results with available pressure and safety cushion • View Supply vs Demand graph with demand point legend • Save completed test records to History • Add project information including associate, project number, project location, test hydrant tag, and flow hydrant tag • Optionally capture test hydrant and flow hydrant coordinates • Attach an image to a saved test record • Export PDF reports with project details, test summary, demand results, graph, location details, friction loss results, and attachment • Estimate friction loss using pipe product, nominal pipe size, inside diameter, pipe length, C-factor, elevation, minor loss, and device/backflow loss • Supports US and SI flow display The Friction Loss tool includes pipe product and nominal pipe size selection with automatic inside diameter lookup. Elevation guidance helps users enter positive values for uphill and negative values for downhill conditions. Hydrant Flow Test Calculator is designed to make field calculations faster, improve documentation consistency, and help organize hydrant flow test information in one place. This app is intended as a calculation and documentation aid. Users are responsible for verifying all inputs, assumptions, calculations, and results according to applicable codes, standards, project requirements, and professional judgment.
Screenshots
Verdict
The clearest difference is review sentiment: Hydrant Flow Test Calculator at 100% against How Deep Is It?'s 57%. Hydrant Flow Test Calculator also leads on rating (5.0 vs 4.1) and update cadence (every 5 weeks vs every 18 months). How Deep Is It?'s advantage is ratings volume (13 vs 3) and iOS requirement (7.0 vs 15.1). On price, ads, in-app purchases and monetization model 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
Both are free to download. Neither carries in-app purchases, so what you see is what you pay.
Hydrant Flow Test Calculator holds the better App Store score, 5.0 against 4.1. Both are backed by a comparable volume of ratings — 13 and 3 respectively. Written reviews point the same way: 57% of How Deep Is It?'s written reviews are positive against 100% of Hydrant Flow Test Calculator's.
How Deep Is It? ships an update every 18 months, Hydrant Flow Test Calculator every 5 weeks. Both last shipped on October 4, 2026.
| Parameter | How Deep Is It? | Hydrant Flow Test Calculator |
|---|---|---|
| Price | Free | Free |
| Rating | 4.1 (13 ratings) | 5.0 (3 ratings) — better |
| Positive reviews | 57.1% of reviews | 100.0% of reviews — better |
| Number of ratings | 13 — better | 3 |
| Update frequency | Every 18 months | Every 5 weeks — better |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Free | Free |
| Devices | iPhone, iPod | iPhone, iPad, iPod — better |
| Requires iOS | 7.0 — better | 15.1 |
| Further details — not scored | ||
| Size | 15 MB | 38 MB |
| Age rating | 4+ | 4+ |
| Developer | Tom Soderling | Saleel Anthrathodiyil |
Customer experience
How Deep Is It?
Hydrant Flow Test Calculator
In-app purchases
How Deep Is It?
No in-app purchases
Hydrant Flow Test Calculator
No in-app purchases
Questions
Is How Deep Is It? free?
Is Hydrant Flow Test Calculator free?
Which has better reviews, How Deep Is It? or Hydrant Flow Test Calculator?
Do How Deep Is It? or Hydrant Flow Test Calculator have ads?
Which is updated more often, How Deep Is It? or Hydrant Flow Test Calculator?
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