# Arca: Daily Learning 365 — General knowledge every day

> General knowledge every day (iPhone/iPad app by kazunari aoki.)

- Source: https://appshunter.io/ios/app/arca-daily-learning-365/id6818716967 (this page in markdown: same URL + `.md`)
- Developer: [kazunari aoki](https://appshunter.io/developer/6774180811)
- Category: Education
- Price: Free with in-app purchases
- Age rating: 4+
- Requires: iOS 26.4 · 54 MB
- Languages: American English, French (France), German (Germany), Italian, Japanese, Korean, Brazilian Portuguese, Chinese (Simplified, China), European Spanish, Chinese (Traditional, Taiwan)
- Released: 2026-10-15
- Data updated: 2026-10-25

## What is Arca?

Arca is 365 days of general knowledge: one short lesson a day, two or three minutes to read. Pick a genre and keep learning every day for a year, from why the sky is blue to how everyday things came to be. Each lesson comes with its own painting, and the day's lesson stays on your Home Screen as a widget.

ONE IDEA A DAY
Why is the sky blue? Why does the Moon always show us the same face? Why do we see what we expect to see? Each lesson starts from an everyday question and walks you to the mechanism with an everyday comparison. One clear idea per lesson, at a length you can keep up every day.

ART MADE FOR EVERY LESSON
Every lesson has its own cover and inline artwork that interprets the idea. Not a diagram: a picture you will want to keep on display.

THE WIDGET
The day's artwork fills the widget, with the date and the lesson title set in colors drawn from the painting (both can be turned off). Tap it to open that day's lesson.
Small, medium and large sizes, plus extra large on iPad.

A FREE FIRST WEEK
For seven days from installation, read one lesson a day from seven genres: science, space, psychology, philosophy, nature, history and earth. The lessons you open stay with you to reread.

365 DAYS OF THE GENRE YOU LOVE
Six packs are available now:
SCIENCE 365: physics, biology, chemistry and discovery.
SPACE 365: from the Moon to the edge of the universe.
PSYCHOLOGY 365: how minds notice, decide and remember.
NATURE 365: forests, oceans, the body and everyday wonders.
HISTORY 365: how everyday things came to be.
EARTH 365: climate, land, oceans and the systems that connect them.
The day you buy is Day 1, and a new lesson and artwork open every day. Lessons you have opened stay available anytime.
Each pack is a one-time purchase. Not a subscription, nothing renews.
Philosophy is in production and coming soon.

CHECKED FACTS
Numbers, dates and names are checked against sources. Where science has no answer yet, the lesson says so.

QUIET BY DESIGN
No account. No ads, analytics or tracking. What you read and your settings stay on your device.

Available in 10 languages: English, Japanese, Korean, Chinese (Simplified and Traditional), Spanish, French, German, Portuguese and Italian. Lessons are translated too.

Terms of Use: https://akiaki1984-alt.github.io/app-legal/arca/terms/
Privacy Policy: https://akiaki1984-alt.github.io/app-legal/arca/privacy/

## Pricing and in-app purchases

Base price: Free.

**One-time purchases**

| Purchase | Price | Type |
| --- | --- | --- |
| EARTH 365 | $5.99 | one-time |
| HISTORY 365 | $5.99 | one-time |
| PSYCHOLOGY 365 | $5.99 | one-time |
| SCIENCE 365 | $5.99 | one-time |
| NATURE 365 | $5.99 | one-time |
| SPACE 365 | $5.99 | one-time |


## Is Arca safe?

Not enough ratings yet to assess Arca.

## Is Arca legit?

Arca: Daily Learning 365 appears legitimate, with a few gaps. The AppsHunter Legitimacy Score for Arca is 65 out of 100 points across 7 verification signals from App Store and developer data.


## Version history (last 4 releases)

### 1.2.0 — 2026-10-23

New pack: EARTH 365. 365 days of climate, land, oceans and the systems that connect them. Where do clouds come from, how are rocks made, why is the sea salty? Also part of the free first week.

### 1.1.1 — 2026-10-19

Clearer store page: Arca is 365 days of general knowledge, one short lesson a day.

### 1.1.0 — 2026-10-16

• Two new packs: NATURE 365 (forests, oceans, the body and everyday wonders) and HISTORY 365 (how everyday things came to be).
• Now in 10 languages, lessons included.
• Swipe a lesson sideways to reach the same day in your other genres.
• The calendar now shows the art of every lesson you have opened, with bookmark marks.

### 1.0.0 — 2026-10-15

No release notes.

## More apps by kazunari aoki

- [静音日和 - 日本の環境音・雨音・睡眠](https://appshunter.io/ios/app/id6774990902)
- [人相診断AI - 16タイプ診断](https://appshunter.io/ios/app/ai-16/id6775012372)
- [StepScape: Walk to Landmarks](https://appshunter.io/ios/app/stepscape-walk-to-landmarks/id6778904496)
- [OFF ME｜悪習慣と距離を置く](https://appshunter.io/ios/app/off-me/id6781712394)
- [Motta? Don't-Forget Checklist](https://appshunter.io/ios/app/motta-dont-forget-checklist/id6782049972)
- [Kokoro Compass](https://appshunter.io/ios/app/kokoro-compass/id6782552223)

All apps by kazunari aoki: https://appshunter.io/developer/6774180811

---

*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-10-25.*