# RectAce (High-Quality Scanner) — Scanner

> High-quality document scanner app for iPhone with advanced image processing. (iPhone/iPad app by Rivac Inc..)

- Source: https://appshunter.io/ios/app/rectace-high-quality-scanner/id432461955 (this page in markdown: same URL + `.md`)
- Developer: [Rivac Inc.](https://appshunter.io/developer/432461958)
- Category: Business, Productivity
- Price: Free with in-app purchases
- Rating: 3.00/5 from 2 App Store ratings · 3 written reviews indexed
- Age rating: 4+
- Requires: iOS 12.0 · 26 MB
- Languages: American English, Japanese
- Released: 2011-04-21
- Data updated: 2026-06-05
- Monetization: free with in-app purchases
- User reviews in markdown: https://appshunter.io/ios/app/rectace-high-quality-scanner/id432461955/reviews.md

## What is RectAce (High?

This application enables you to use your iPhone as a scanner. Works not only with documents, receipts, business cards, notebooks, catalogs and other paper-based media, but also with the likes of whiteboards, posters, and train schedules. Use this application to obtain high-quality images.

Upon importing images contained in your iPhone's Photo Album or those taken with your device's camera, this application automatically recognizes the frame (outline) in the pictures, renders them so that they appear to be viewed from the front, and even enhances their attractiveness through applying color correction. This enables a level of image quality reminiscent of something taken with a scanner.

* Price may change without prior notice.

【Features】

The following represent a sample of the features offered by this application.

(1) Frame recognition (Detection of rectangular fields)
This application goes beyond simply recognizing four corner points and simultaneously detects the degree of distortion (the barrel distortion unique to cameras). Additionally, the application captures multiple candidate frames, thereby offering enhanced work efficiency relative to cases in which only one frame can be obtained.

(2) Front-facing adjustment
Photos taken at a diagonal are adjusted to make them appear to have been taken from the front. Distortion correction can also be carried out using the degree of distortion obtained through the frame recognition feature mentioned in (1) above.

(3) Color correction
This feature enables fine images to be taken in color as well as in black-and-white. Images are processed to ensure that even small characters are vividly reproduced. Furthermore, should shadows be present in the background of a photo, the application uses a background color modification function to eliminate only the shadows while preserving any characters or graphics.

【Main Functions】

■Camera (Anti-camera shake measures)
-Function that takes multiple continuous shots and chooses the sharpest image (BSS:Best-Shot Selection function)
-“Takes photo when shaking stops” function

■Frame recognition
-Detection of rectangular fields
-Distortion recognition (Can be toggled)
-Function that obtains multiple frame candidates

■Geometric correction
-Front facing adjustment
-Distortion correction (Can be toggled)
-Edge smoothing function

■Color correction
-Function that obtains fine images.
-Brightness adjustment
-Background color modification (Function that removes shadows and restores colors that disappeared)
-Function that thickens up thin characters.

■Images
-Elimination of salt-and-pepper noise (Elimination of unwanted spotty phenomenon)
-Ability to cut out designated rectangular fields
-Slight cutting of image periphery (Used when contour lines remain on the image)
-Ability to designate horizontal-to-vertical ratio of image (Typically handled automatically with option to designate)

■Batch processing
- Function that shoots multiple pages continuously.
- Function that recognizes frames, makes photos face the front, and corrects colors collectively.

■SubFolders (in App)
-Creates SubFolders in a folder.
-Expands a folder.

■AirPrint
-Prints with one image in one page and 100% magnification.
-By purhasing Printer Extensions (In-App Purchase), you can use the functions of printer extensions.

■Sending
-Sending via email in JPEG or PDF format
-Ability to forward to Evernote, GoogleDrive, Dropbox and OneDrive as JPEG or PDF format
-Designating the maximum file size upon sending images

【Printer Extensions (In-App Purchase)】
Main functions are as follows:

・Prints with multiple images in one page.
・Specifies print-magnification.
・Sends print-images as JPEG or PDF
(To : Camera roll, Other Apps, Clouds)

※Printers need to support AirPrint.
※Clouds : Evernote, Dropbox, Google Drive, BOX, OneDrive.

## Key features

- Automatic frame recognition
- Distortion correction
- Color correction and enhancement
- Anti-camera shake measures
- Batch processing for multiple pages
- Image cropping and resizing

## Pricing and in-app purchases

Base price: Free.

**One-time purchases**

| Purchase | Price | Type |
| --- | --- | --- |
| Printer Extensions | Free | one-time |


## Recent user reviews (3 of 3)

All indexed reviews: https://appshunter.io/ios/app/rectace-high-quality-scanner/id432461955/reviews.md

### 1/5 — Only works 3 times?

*2013-03-22*

It worked great for three times, but now it won't send to my Evernote Acct. App help site is all in Japanese so I don't know where to get assistance.

### 5/5 — Wow!

*2012-02-07*

I have no clue about what they are doing under the hood, but the quality of these scans are superb. I own most of the popular scanning apps and have done a variety of tests under different lighting conditions and the processing RectAce uses consistently produces the best results.

Update:
Even better and still, hands down the best quality scanner to date (I've tried and compared most of them). Dropbox, Evernote and Google Docs support now as well, since last version 1.0.0 review.

There is Evernote support, but what would put this app at the top of the tree would be:
1. In-App saves 
2. Dropbox support (Update: email from developer states this is coming in next update - yay!)

It's pretty much perfect as it is and there are workarounds (email PDF etc.) but get those two things right and this would be the premier scanner on the app store without question.

Update: In-App saves are coming later in the year apparently, however after using the app for some time, it's not that crucial and the files can be around 1Mb (really high quality default, but you can adjust the size) so maybe it's not so practical.

### 5/5 — Fantastic App!

*2011-05-07*

This is a must have for folks that have to capture data on the fly. I use it primarily to transfer mindmaps from large whiteboards, and it works flawlessly!

## Frequently asked questions about RectAce (High

### What types of documents can RectAce scan?

RectAce can scan various paper-based media including documents, receipts, business cards, notebooks, and catalogs. It also works with items like whiteboards and posters.

### How does RectAce improve scan quality?

RectAce automatically recognizes document frames, corrects distortion, and applies color correction to enhance image quality, making scans look like they were taken with a dedicated scanner.

### Does RectAce have ads?

No, RectAce does not contain advertisements. It is a free app with optional in-app purchases.

### What devices is RectAce compatible with?

RectAce is available for iPhone and iPod devices. It requires iOS 4.0 or later.

### How often is RectAce updated?

The latest version, 6.0.0, was released on April 22, 2021. Update frequency can vary, but the app has been available since 2011.

### What are the main functions of RectAce?

Key functions include advanced frame recognition, front-facing adjustment for diagonal photos, color correction, anti-camera shake measures, and batch processing for continuous shooting.

### What is the user rating for RectAce?

RectAce has a rating of 3.0 stars from 2 ratings. This indicates a mixed user reception based on the available data.

### Is RectAce free to use?

Yes, RectAce is free to download and use. There are in-app purchases available for additional features or content.

## Version history (last 5 releases)

### 6.0.0 — 2021-04-22

- Supports Retina High-Resolution Display.

### 5.7.4 — 2018-02-01

This app has been updated by Apple to display the Apple Watch app icon.

- bug fixed

### 5.7.3 — 2017-12-21

- bug fixed

### 5.7.2 — 2017-10-26

- Camera focus bug fixed.

### 5.7.0 — 2017-10-14

-bug fixed

## More apps by Rivac Inc.

- [FrontShot](https://appshunter.io/ios/app/frontshot/id1434295595)

All apps by Rivac Inc.: https://appshunter.io/developer/432461958

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*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 2026-06-05.*