# Act Study vs Obo | One By One

The clearest difference is update cadence: Obo | One By One at weekly against Act Study's monthly. Act Study's advantage is device support (3 vs 1) and iOS requirement (15.2 vs 17.0). On price, ads and in-app purchases there is nothing between them.

Both are free to download. Act Study sells 1 one-off in-app purchase and Obo | One By One sells 6 one-off in-app purchases. Whichever you choose, the download price is not the number that matters.

Act Study ships an update monthly, Obo | One By One weekly. The most recent releases landed on October 8, 2026 and September 29, 2026 respectively.

## The numbers

| Metric | Act Study | Obo | One By One |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[5.0 (1 ratings)](https://appshunter.io/ios/app/obo-one-by-one/id6758606356/reviews)** |
| Number of ratings | — | **1** |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Monthly | **Weekly** |
| Monetization | — | Free with in-app purchases |
| Size | 104 MB | 49 MB |
| Requires iOS | **15.2** | 17.0 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [ANYONE INC.](https://appshunter.io/developer/1577319263) | [Luthfi Misbachul Munir](https://appshunter.io/developer/1745283652) |

## What reviewers say

### Act Study

[App page](https://appshunter.io/ios/app/act-study/id6469045101)

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| IQ TEST | Free | one-time |


### Obo | One By One

[App page](https://appshunter.io/ios/app/obo-one-by-one/id6758606356)

Master Japanese with a personal language learning companion. It uses smart spaced repetition and AI to help you learn vocabulary, grammar, and kanji efficiently. Offers flexible study options for beginners, travelers, and JLPT students.

**Highlights:** Smart Spaced Repetition (FSRS v5), AI-Powered Smart Add for flashcards, Hiragana & Katakana guide, JLPT N5-N1 template decks, Anki deck import, Offline study support, Dark mode

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases (6)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Starter AI Coins | $1.99 | one-time |
| Premium N4 Deck | $2.99 | one-time |
| Pro AI Coins | $2.99 | one-time |
| Premium N5 Deck | $3.99 | one-time |
| Ultimate AI Coins | $4.99 | one-time |
| Premium N3 Deck | $9.99 | one-time |


## Frequently asked questions

### Is Act Study free?

Act Study is free to download, with in-app purchases available.

### Is Obo | One By One free?

Obo | One By One is free to download, with in-app purchases available.

### Do Act Study or Obo | One By One have ads?

Neither Act Study nor Obo | One By One shows ads.

### Which is updated more often, Act Study or Obo | One By One?

Act Study ships an update monthly, and Obo | One By One weekly. Most recently, Act Study was updated on October 8, 2026 and Obo | One By One on September 29, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*