Comparison

phyphox vs Monad Calendar Clock

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

phyphox

Unlock your phone's sensors for scientific exploration. Conduct pre-built experiments or create your own using accelerometers, magnetometers, and more. Analyze and export data in various formats for further study.

Highlights
  • Pre-defined experiments
  • Data export (CSV, TSV, Excel)
  • Web-based remote control
  • Custom experiment editor
  • Access to phone sensors
  • Advanced analysis functions
Features
Read full description

Did you know that you are carrying a 3D magnetometer? That you can use your phone as a pendulum to measure earth's local gravitational acceleration? That you can turn your phone into a sonar? phyphox gives you access to the sensors of your phone either directly or through ready-to-play experiments which analyze your data and let you export raw data along with the results for further analysis. You can even define your own experiments on phyphox.org and share them with colleagues, students and friends. Selected Features: • A selection of pre-defined experiments. Just press play to start. • Export your data to a range of widely used formats • Remote-control your experiment through a web interface from any PC on the same network as your phone. No need to install anything on those PCs - all you need is a modern web browser. • Define your own experiments by selecting sensor inputs, defining analysis steps and creating views as an interface using our web-editor (http://phyphox.org/editor). The analysis consists of just adding two values or using advanced methods like Fourier transforms and crosscorrelation. We offer a whole toolbox of analysis functions. Sensors supported: • Accelerometer • Magnetometer • Gyroscope • Pressure • Microphone • Proximity • GPS • Camera • LiDAR/ToF *some sensors are not present on every phone. Export formats • CSV (Comma separated values) • TSV (Tab-separated values) • Excel (if you need other formats, please let us know) This app has been developed at the 2nd Institute of Physics A at the RWTH Aachen University.

About

Monad Calendar Clock

This app visualizes time through planetary and celestial movements, contrasting natural rhythms with mechanical time. It offers unique perspectives on Earth's position in space and time, showing star and planet locations, seasonal changes, and lunar phases.

Highlights
  • Planetary time and date display
  • Celestial ring visualization
  • Heliocentric and Geocentric modes
  • Star and planet location tracking
  • Seasonal and lunar phase progression
  • Twilight and sunrise/sunset times
  • Event scheduling
Features
Read full description

MONAD does something that no other clock or calendar does; it tells the planetary time and date – the solar day, lunar month & seasonal year. MONAD reveals your unique place (and perspective) in planet-centered space and time. MONAD demonstrates the biorhythms of the Earth’s biosphere, and it integrates two types of time: 1) Natural time, which is cyclic, variable, and alive, with 2) Mechanical time, which is linear, highly regular, abstract and artificial. MONAD represents a paradigm shift of planetary proportions; A New Paradigm of Time With MONAD, you see the natural rhythms of time­ proceeding in endless circles and spirals. MONAD shows the location of the stars and planets; what’s visible at night from your location on Earth. MONAD shows the progression of the four seasons and the phases of the Moon; the obliquity of the ecliptic and the Earth’s circle of illumination, and a Twilight Dial tells you the time of Sun rise and Sun set at any latitude and time of year. MONAD shows the agricultural biorhythms of the Earth’s photosynthetic biosphere. MONAD restores the Earth, and the Earth’s biorhythms and biosphere, back to the center of our collective attention and awareness. With MONAD you see the Earth globe from an unusual perspective; the north (or south) polar axial perspective. MONAD automatically places a time zone-spanning Hour Hand at your location on the globe, marking your longitude & latitude, and you see all 24 time zones, all around the globe at the same time, the whole world interconnected. MONAD has four main Modes of operation. Geocentric (Geo) Mode features planet Earth at the center of a time and date-telling, 3-dimensional celestial ring. The algorithms and programming which drive all of the astronomical activity is based on a Sun-centered and highly accurate model of the solar system which you can access in Heliocentric (Helio) Mode. Accelerate through time, into the past or future, and watch how the configuration of the solar system changes. Shift back and forth from Geo to Helio Modes, and it’s easy to see how the two perspectives are related. It’s easy to see how and why the planets have apparent retrograde activity from an Earth-centered perspective. There is so much to explore and learn in MONAD. Astro Mode features a 2-dimensional Calendar-Clock face, which makes it possible to set the time by dragging the hour hand around the dial, or you can set the date by dragging the calendar band, or zodiac band, past the Sun’s meridian or date indicator fixed at noon at the top of the dial. A Table at the top of the screen lists the precise location of the Sun, Moon and planets at any time and date, so basically this Astro screen is equivalent to an astronomy or astrology chart, at any moment in time. Astro Mode will eventually feature a Scientific Astrology Program and an Educational Astronomy Program. Event Mode is where you record and schedule personal events, in the context of important and memorable planetary events we all share. Color-coded Event Wedges are shown in the context of the 4 corners of a solar day (Sun rise, noon, Sun set & midnight), the 4 corners of a lunar month (full and dark Moon, waxing and waning half Moons), and the 4 corners of a seasonal year (equinoxes & solstices). Another unique feature of MONAD is that you can record events “in the Now,” which encourages more presence in your life. A Health Event Mode allows you to see your personal, endocrine biorhythms in the context of planetary biorhythms we all share. The 24 hour circadian Calendar-Clock face is ideally suited to organize and display health events. If you choose to have MONAD integrate with the Apple Health app (HealthKit); then health data (e.g. Sleep period and Steps) read from HealthKit is used for display within the MONAD app. MONAD is beautiful, educational & transformative, and it will change the way you see the world around you, and your place within it. MONAD – A New Paradigm of Time.

Screenshots

phyphox4 screens
Monad Calendar Clock4 screens

Verdict

The call

The clearest difference is review sentiment: phyphox at 79% against Monad Calendar Clock's 22%. phyphox also leads on price (Free vs $0.99) and rating (4.6 vs 3.7). Monad Calendar Clock's advantage is update cadence (every 6 weeks vs every 3 months). On ads, in-app purchases, device support and iOS requirement 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

CostPrice · In-app purchases · Ads · Monetization

phyphox is free to download; Monad Calendar Clock costs $0.99 up front. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

phyphox holds the better App Store score, 4.6 against 3.7. That said, the two scores are not equally well evidenced: phyphox has 272 ratings behind it against 14, so its average is the more settled of the two. Written reviews point the same way: 79% of phyphox's written reviews are positive against 22% of Monad Calendar Clock's.

UpkeepUpdate frequency

phyphox ships an update every 3 months, Monad Calendar Clock every 6 weeks. The most recent releases landed on September 27, 2026 and September 6, 2026 respectively.

Scorecard6 real differences · 4 level
phyphox versus Monad Calendar Clock: the parameters behind the verdict, then further details
ParameterphyphoxMonad Calendar Clock
PriceFree — better$0.99
Rating4.6 (272 ratings) — better3.7 (14 ratings)
Positive reviews78.9% of reviews — better22.2% of reviews
Number of ratings272 — better14
Update frequencyEvery 3 monthsEvery 6 weeks — better
AdsNoNo
In-app purchasesNoNo
MonetizationFree — betterPaid
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS12.0 — better13.0
Further details — not scored
Size19 MB266 MB
Age rating4+4+
DeveloperRWTH Aachen UniversityEarth at the Center LLC

Customer experience

phyphox

All ratings272 ratings
Positive89.7%
Neutral3.7%
Negative6.6%
Written reviews265 reviews
Positive78.9%
Neutral3.0%
Negative18.1%

Monad Calendar Clock

All ratings14 ratings
Positive64.3%
Neutral7.1%
Negative28.6%
Written reviews9 reviews
Positive22.2%
Neutral11.1%
Negative66.7%

Bugs and requests

phyphox

Reported bugs

21 issues
  • App crashes on older devices
  • Barometer not working on iOS 17.4
  • Network error: Generic error
  • Sound measurement curve disappears
  • App crashes frequently
Show 16 more
  • Cannot be opened on iPhone 6
  • Light sensor not implemented
  • Recording stops when phone is locked or app is minimized
  • Green lines on screen and faded to black after using barometer sensor
  • WLAN not working after using the app
  • Pressure no longer displayed on iOS 17.5
  • Barometer not working on iOS 17.4
  • Latest version cannot be opened on iPhone 6
  • Sound chronometer reset button not working
  • iPad destroyed after update
  • App displays Russian language by default
  • Experiments not working on iPhone 7
  • Magnetometer not working after update on iPhone 5s
  • GPS shows 0 satellites with 6m accuracy
  • App claims iPhone 11 is comparable to a low-cost tablet
  • App crashes every time

Requested features

33 requests
  • Add infrasound detector
  • More units of measurement (G-force, PSI, feet)
  • NFC/RFID support
  • In-app bug report feature
  • Allow other sensors via USB-C
Show 28 more
  • Ability to plug in external sensors
  • Slo-mo recording with timestamps
  • Add attitude sensor (roll, pitch, yaw)
  • Integration with Apple Shortcuts
  • Ability to record audio/dB simultaneously with other sensors
  • Adjustable sampling frequency for all sensors
  • Dark mode option
  • Experiment editor integrated into the app
  • More documentation for the editor
  • Ability to form averages
  • Support for older iPhones (iPhone 6)
  • Add GPS satellite count display
  • Add speedometer functionality
  • Add Lux measurement using light sensor/camera
  • Ability to play recorded audio
  • Limit input for sound analyzers (dB/Hz range)
  • Wi-Fi and RF module access for EMF analysis
  • iWatch integration
  • Improve audio generator capability
  • Allow background/screen locked recording
  • Add light sensor functionality
  • Change units of measurement
  • Add more precise measurements for static cases
  • Add FFT and spectral generation for accelerometer
  • Support for older devices
  • Improve UI/UX for new users
  • Add support for more languages
  • Add a donate option

Monad Calendar Clock

Not enough reviews yet to summarise bugs or requests.

In-app purchases

None

phyphox

No in-app purchases

None

Monad Calendar Clock

No in-app purchases

Questions

Is phyphox free?
phyphox is free to download, with no in-app purchases.
Is Monad Calendar Clock free?
Monad Calendar Clock costs $0.99, with no in-app purchases.
Which has better reviews, phyphox or Monad Calendar Clock?
phyphox is rated higher. phyphox averages 4.6 out of 5 from 272 ratings, while Monad Calendar Clock averages 3.7 from 14 ratings.
Do phyphox or Monad Calendar Clock have ads?
Neither phyphox nor Monad Calendar Clock shows ads.
Which is updated more often, phyphox or Monad Calendar Clock?
phyphox ships an update every 3 months, and Monad Calendar Clock every 6 weeks. Most recently, phyphox was updated on September 27, 2026 and Monad Calendar Clock on September 6, 2026.

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