# Gengou Lib vs Doc Align

The clearest difference is in-app purchases: Gengou Lib at none against Doc Align's 1. Gengou Lib also leads on iOS requirement (13.0 vs 15.0). Doc Align's advantage is update cadence (monthly vs every 61 months). On price, ads and device support there is nothing between them.

Both are free to download. Doc Align sells 1 one-off in-app purchase. Gengou Lib asks for nothing beyond the download.

Gengou Lib ships an update every 61 months, Doc Align monthly. The most recent releases landed on August 13, 2026 and September 2, 2026 respectively.

## The numbers

| Metric | Gengou Lib | Doc Align |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[2.5 (2 ratings)](https://appshunter.io/ios/app/gengou-lib/id284830543/reviews)** | — |
| Number of ratings | **2** | — |
| Positive reviews | 84.5% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | Yes | Yes |
| Update frequency | Every 61 months | **Monthly** |
| Monetization | Free | — |
| Size | 6 MB | 18 MB |
| Requires iOS | **13.0** | 15.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Masayuki Akamatsu](https://appshunter.io/developer/284722836) | [Kazuhisa Kobayashi](https://appshunter.io/developer/1580882000) |

## What reviewers say

### Gengou Lib

[App page](https://appshunter.io/ios/app/gengou-lib/id284830543)

Quickly convert between Japanese era names and Christian era years. Features include era and year searching, period and era pickers, and the ability to display the current year in either system. Texts can be shown in Japanese or English.

**Highlights:** Era and year search, Period picker, Era picker, Christian era year picker, Japanese era year picker, Show this year button, Multi-language text display

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

**In-app purchases:** none


### Doc Align

[App page](https://appshunter.io/ios/app/doc-align-perspective-fixer/id6748571837)

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Remove Ads | $4.99 | one-time |


## Frequently asked questions

### Is Gengou Lib free?

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

### Is Doc Align free?

Doc Align is free to download, with in-app purchases available.

### Do Gengou Lib or Doc Align have ads?

Both Gengou Lib and Doc Align show ads.

### Which is updated more often, Gengou Lib or Doc Align?

Gengou Lib ships an update every 61 months, and Doc Align monthly. Most recently, Gengou Lib was updated on August 13, 2026 and Doc Align on September 2, 2026.

---

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