Comparison

Mars Book vs pt

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

Head to head

About

Mars Book

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The Mars Book is an app that is dedicated for observing Mars which will make close approach in summer 2020. Mars will come close to Earth from September 2020 through October 2020. Closest approach will take place on October 6, 2020. Mars Book is a highly useful Mars observing app which will indicate the location of Mars visible in the sky. It shows you why Mars Close Approach will take place, and it is explained readily using animated illustrations and star charts at a viewpoint from outer Space. Mars Close Approaches taking place 23 times from the year 2003 through 2050 will be displayed and apparent retrograde motion of Mars will be displayed. Enjoy Mars Close Approach this summer with the Mars Book app!

About

pt

Features

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This app enables the user to use the UCAN progress test on iOS devices.

Screenshots

Mars Book3 screens

pt2 screens

Verdict

The call

The clearest difference is update cadence: pt at every 2 months against Mars Book's every 13 months. Mars Book's advantage is iOS requirement (9.0 vs 11.0). 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

Mars Book ships an update every 13 months, pt every 2 months. The most recent releases landed on September 28, 2026 and October 2, 2026 respectively.

Scorecard2 real differences · 4 level

Mars Book versus pt: the parameters behind the verdict, then further details
Parameter	Mars Book	pt
Price	Free	Free
Update frequency	Every 13 months	Every 2 months — better
Ads	No	No
In-app purchases	No	No
Devices	iPhone, iPad, iPod	iPhone, iPad, iPod
Requires iOS	9.0 — better	11.0
Further details — not scored
Size	14 MB	1 MB
Age rating	4+	12+
Developer	Vixen Co.,Ltd.	Konstantin Brass

In-app purchases

None

Mars Book

No in-app purchases

None

pt

No in-app purchases

Questions

Is Mars Book free?

Mars Book is free to download, with no in-app purchases.

Is pt free?

pt is free to download, with no in-app purchases.

Do Mars Book or pt have ads?

Neither Mars Book nor pt shows ads.

Which is updated more often, Mars Book or pt?

Mars Book ships an update every 13 months, and pt every 2 months. Most recently, Mars Book was updated on September 28, 2026 and pt on October 2, 2026.