Comparison

Nautilus vs Cat's Study

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

Head to head
About

Nautilus

Features
Read full description

For the hours you spend studying or working alone. While you dive, the apps you chose truly won't open. Exams, certifications, deep work included. Nautilus folds three things into one action: dive. REAL BLOCKING, AT THE OS LEVEL Tap to dive, and the apps you chose (social, YouTube, etc.) are shielded on the spot via Screen Time. Not a reminder โ€” while you're diving, those apps genuinely won't open. Block sets change per focus type (e.g. Reading vs. Coding). DUMP A DISTRACTION IN 3 SECONDS A stray "I need to do that" mid-session? Jot it down from the Lock Screen or Dynamic Island in about 3 seconds, without leaving focus. Everything you dumped is waiting for you when you surface. SURFACE, AND IT'S ALREADY A JOURNAL When you surface, that session becomes a log entry automatically โ€” what you dove into, how long, what distractions you dumped. No manual logging. DESIGNED FOR ZERO GUILT No red badges. A zero-minute day isn't punished. "Depth," the number that reflects your focus quality, only ever goes up. Blocking relies on the device's Screen Time framework.

About

Cat's Study

Features
Read full description

Cat's Study is a study timer where you focus alongside a cat. Start a task and the cat in the room opens its book too. It rests when you rest and dozes off when you're done. Homework, exams, deep work or reading: it all feels a little less lonely with company. FOCUS TIMER - Stopwatch or Pomodoro, with focus and break lengths set to the minute. - Get notified when it's time to focus or take a break. - Leave the screen alone while you focus and the room dims, with only the timer showing. Handy on a desk stand. TASK PLANNER - Tap โ–ถ next to any of today's tasks to start right away. - Sort tasks into categories like Study or Work, and set daily ones to repeat. - Can't decide? Tap "Just start" and the cat comes up with a task for you. STUDY TRACKER - Daily, weekly and monthly focus time, broken down by category. - Focus 5+ minutes in one go each day to build a streak. - Share your records as an image. ROOM AND SOUNDS - Play rain sounds, thunder, library ambience or lofi music on the turntable, even with the screen off. - Eight room themes, including Cafรฉ in the Rain, Cherry Blossom Study and Spaceship Study. - Earn coins from check-ins, focus sessions and streaks to dress up your cat and its room. NO PRESSURE - Start without signing in, or sign in to keep your records on any device. - Every feature is free, with no in-app purchases. No ads while you focus. - Dark mode supported.

Screenshots

Nautilus4 screens
Cat's Study4 screens

Verdict

The call

The clearest difference is ads: Nautilus at none against Cat's Study's shown. Cat's Study's advantage is iOS requirement (16.6 vs 18.0). On price, in-app purchases and device support 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

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

Scorecard2 real differences ยท 4 level
Nautilus versus Cat's Study: the parameters behind the verdict, then further details
ParameterNautilusCat's Study
PriceFreeFree
Update frequencyEvery 5 daysโ€”
AdsNo โ€” betterYes
In-app purchasesNoNo
DevicesiPhone, iPadiPhone, iPad
Requires iOS18.016.6 โ€” better
Further details โ€” not scored
Size36 MB140 MB
Age rating4+4+
DeveloperHIROTO IGUCHILo-Fi Labs Inc.

In-app purchases

None

Nautilus

No in-app purchases

None

Cat's Study

No in-app purchases

Questions

Is Nautilus free?
Nautilus is free to download, with no in-app purchases.
Is Cat's Study free?
Cat's Study is free to download, with no in-app purchases.
Do Nautilus or Cat's Study have ads?
Cat's Study shows ads; Nautilus does not.

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