Comparison

Clavis vs Surya Time

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

Head to head
About

Clavis

Features
Read full description

Planetary Clock is a precise, beautifully simple planetary-hours clock. Since antiquity, each day and night has been divided into twelve unequal hours, each governed by one of the seven classical planets in the Chaldean order. Planetary Clock computes these hours with astronomical accuracy from the true sunrise and sunset in the city you choose. โ€ข Current planetary hour โ€” see which planet rules right now, with a live countdown to the next hour. โ€ข Apple Watch โ€” the ruling planet and the minutes left in this hour, right on your watch face and in the Smart Stack. Hours are computed on the watch, so it works even when your iPhone is out of reach. โ€ข Ruler of the day โ€” the classical planet that governs today. โ€ข Upcoming hours โ€” a clear timeline of the planetary hours ahead, from sunrise to sunset and through the night. โ€ข Moon phase โ€” the current phase and illumination of the Moon. โ€ข Monthly calendar โ€” lunar phases and planetary hours at a glance. โ€ข 3D chart โ€” your birth chart rendered in three dimensions, with transits and aspects. โ€ข Sync across devices โ€” sign in and your calendar and chart settings follow you. Planetary Clock is a subscription app. A monthly or annual plan unlocks everything, with a free trial when your Apple Account is eligible. No ads, and no tracking. Signing in with Apple or Google keeps your data in step across your devices. You pick your city by searching for it โ€” the app does not use GPS โ€” and every planetary hour is computed from that city's coordinates and time zone, so the same place is used on every device. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

About

Surya Time

This app redefines time by tracking the sun's position relative to your local horizon. It divides daylight into natural hours, showing your progress through the day and accounting for your actual skyline. Features include a vantage map for extended sunsets and offline functionality.

Highlights
  • Daylight-based time division
  • Actual skyline visualization
  • Vantage Map for extended sunsets
  • Offline functionality
  • Home and lock screen widgets
  • True local solar noon
  • Sky pointer for sun/moon location
Features
Read full description

How much daylight have you got left? Surya Time answers the way people did before anyone thought of time zones. It takes the light you are actually given today, from sunrise to sunset, and divides it into twelve hours; then it does the same with the night. An hour here is as long as the light allows. In June yours will run past sixty-six minutes, and by December they will have shrunk towards forty, and neither figure is a rounding error. It is simply what the sky did. All of it is worked out on the phone from your own coordinates, which means that noon arrives when the sun is over you, and not when it is over the city your time zone happens to be named after. The dial shows you what the day has spent and what it still owes you: seven hours and fifty-five minutes of light, say, and the hour you are presently standing in. Sunrise and sunset are given on the clock the place itself keeps, so a city you have pinned reads as a local would read it. And the day does not end at a flat horizon. Download the ground around you and the app draws the skyline you actually stand in front of, with the summits on it named and measured: Mont Blanc de Courmayeur at 4,748 m, and the nearer, lower hills that take more of your evening precisely because they are close. A ridge to the west can be worth a quarter of an hour, and now you can see which one is taking it. Which raises a practical question, so there is an answer for that as well. The Vantage Map ranks the ridges and lookouts around you by how much more sunset each would give back โ€” a hundred and nine minutes for a summit fifteen kilometres off, if that is a walk you fancy โ€” and it shows you the gain before you set out. Choose an area of thirty, sixty or two hundred kilometres, download its elevation once, and the horizon keeps working with no signal at all. There are five widget sizes for the home screen and the lock screen, and each one asks for its own fix, so a phone that has flown overnight has already caught up before you open the app. If you want to know how far your watch has drifted from the sun, the app will tell you, and it will tell you where the minutes went: some are the price of your longitude inside a time zone drawn for somebody else, and the rest belong to the Earth, whose orbit is an ellipse and whose axis is tilted. Some days twelve hours of sixty is exactly what you want. On other days you would rather simply hear that two fifths of the daylight has gone, and the app will say it that way instead. The hours can be named in Greek, in Latin, or in plain English, whichever sounds least like an instrument panel to you. When you lose the moon, hold the phone up and the app will point at it. Sun or moon, the bearing is worked out for the ground you are standing on rather than for the centre of the Earth, which matters more than it sounds: close to the horizon the difference between the two is wider than the moon itself. There is a map as well, showing where the daylight is falling this second, with the line between day and night drawn true and your own place marked upon it. The moon is drawn as a real terminator rather than an emoji, and the colours follow the sun's true altitude, so the screen tends to look like the hour it is describing. You can pin a city if you would sooner read somebody else's sky. There is no account, no sign-in and nothing that tracks you.

Screenshots

Clavis4 screens
Surya Time4 screens

Verdict

The call

The clearest difference is price: Clavis at Free against Surya Time's $0.99. Clavis also leads on device support (3 vs 1). Surya Time's advantage is update cadence (every 2 days vs every 5 days). On ads, in-app purchases and iOS requirement there is nothing between them.

Scored on Price ยท Rating ยท Positive reviews ยท Number of ratings ยท Update frequency ยท Ads ยท In-app purchases ยท Monetization ยท Best chart rank ยท Devices ยท Requires iOS

CostPrice ยท In-app purchases ยท Ads ยท Monetization

Clavis is free to download; Surya Time costs $0.99 up front. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

Clavis ships an update every 5 days, Surya Time every 2 days. Both last shipped on October 5, 2026.

Scorecard3 real differences ยท 5 level
Clavis versus Surya Time: the parameters behind the verdict, then further details
ParameterClavisSurya Time
PriceFree โ€” better$0.99
Positive reviewsโ€”100.0% of reviews
Update frequencyEvery 5 daysEvery 2 days โ€” better
AdsNoNo
In-app purchasesNoNo
Monetizationโ€”Free
DevicesiPhone, iPad, Apple Watch โ€” betteriPhone
Requires iOS16.2 โ€” better17.0
Further details โ€” not scored
Size31 MB4 MB
Age rating4+4+
DeveloperPedro Henrique Oliveira SousaMax Schleining

In-app purchases

None

Clavis

No in-app purchases

None

Surya Time

No in-app purchases

Questions

Is Clavis free?
Clavis is free to download, with no in-app purchases.
Is Surya Time free?
Surya Time costs $0.99, with no in-app purchases.
Do Clavis or Surya Time have ads?
Neither Clavis nor Surya Time shows ads.
Which is updated more often, Clavis or Surya Time?
Clavis ships an update every 5 days, and Surya Time every 2 days. Most recently, Clavis was updated on October 5, 2026 and Surya Time on October 5, 2026.

Other comparisons