Comparison

Relativity Calendar vs Rheba Clock

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

Head to head
About

Relativity Calendar

This app redefines how you view dates by allowing you to express any day relative to any month. See custom dates like 'May 32nd' or 'March 93rd' at a glance. It offers home screen widgets and Apple Watch complications for easy access.

Highlights
  • Express dates relative to any month
  • Home screen widgets with color customization
  • Apple Watch complications
  • iOS 16 Lock Screen widgets
  • Track custom dates and holidays
Features
Read full description

Relativity Calendar is an app that tells you what day it is, relative to any month. For example, June 1st can also be written as May 32nd or March 93rd. Set any month you want, and you'll be able to see it at a glance in your widgets and Apple Watch! Whether it's the month of your birth, an important holiday, or Truck Month, Relativity Calendar will (more or less) help you keep track. Features: - Pick any month, even if it doesn't make sense. Especially if it doesn't make sense. - Full support for home screen widgets, with full color customization - Full support for Apple Watch, including complications - Supports iOS 16 Lock Screen widgets.

About

Rheba Clock

Read full description

This is a clock/watch app that keeps time in minutes and seconds in a unique way. Each circle represents a unit of time. Check out the seconds view to figure out the pattern

Screenshots

Relativity Calendar4 screens

Verdict

The call

The clearest difference is update cadence: Rheba Clock at daily against Relativity Calendar's every 2 months. Rheba Clock also leads on iOS requirement (13.0 vs 15.0). On price, ads, in-app purchases and device support 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

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

Relativity Calendar ships an update every 2 months, Rheba Clock daily. The most recent releases landed on September 28, 2026 and October 6, 2026 respectively.

Scorecard2 real differences · 8 level
Relativity Calendar versus Rheba Clock: the parameters behind the verdict, then further details
ParameterRelativity CalendarRheba Clock
PriceFreeFree
Rating4.9 (17 ratings) — better—
Positive reviews100.0% of reviews—
Number of ratings17 — better—
Update frequencyEvery 2 monthsDaily — better
AdsNoNo
In-app purchasesNoNo
MonetizationFree—
DevicesiPhone, iPod, Apple WatchiPhone, iPod, Apple Watch
Requires iOS15.013.0 — better
Further details — not scored
Size3 MB0 MB
Age rating4+4+
DeveloperJonathan ColeAdam Trubnikov

In-app purchases

None

Relativity Calendar

No in-app purchases

None

Rheba Clock

No in-app purchases

Questions

Is Relativity Calendar free?
Relativity Calendar is free to download, with no in-app purchases.
Is Rheba Clock free?
Rheba Clock is free to download, with no in-app purchases.
Do Relativity Calendar or Rheba Clock have ads?
Neither Relativity Calendar nor Rheba Clock shows ads.
Which is updated more often, Relativity Calendar or Rheba Clock?
Relativity Calendar ships an update every 2 months, and Rheba Clock daily. Most recently, Relativity Calendar was updated on September 28, 2026 and Rheba Clock on October 6, 2026.

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