Download Usugami for Android

Three editions

Every edition converts images, Word, PowerPoint, Excel and EPUB files to PDF and has every PDF tool, fully offline. They differ in text recognition (OCR). If you’re not sure, take Usugami.

Usugami
Recommended

Usugami.apk, about 3 MB

Images, Word, PowerPoint, Excel and EPUB to PDF, and every PDF tool
Fully offline

Text recognition (OCR) for searchable PDFs
Runs on your phone through Google Play services, which downloads Google’s text-recognition model the first time you use it.

Internet needed
Only for text recognition, the first time you use each language

Needs Google Play services
Only for text recognition

Google code inside
Google’s ML Kit and Play services libraries, for text recognition

Works on
Android 8.0 or newer

Pick it if
You’re not sure

Download Usugami.apk
Usugami Lite

Usugami-lite.apk, about 2.8 MB

Images, Word, PowerPoint, Excel and EPUB to PDF, and every PDF tool
Fully offline

Text recognition (OCR) for searchable PDFs
Not included

Internet needed
Never

Needs Google Play services
No

Google code inside
None

Works on
Android 8.0 or newer

Pick it if
You don’t need text recognition and want the smallest app, with no Google code at all

Download Usugami-lite.apk
Usugami OCR

Usugami-ocr.apk, about 14 MB: the recognition engine and models are inside

Images, Word, PowerPoint, Excel and EPUB to PDF, and every PDF tool
Fully offline

Text recognition (OCR) for searchable PDFs
Open source and built into the app (PaddleOCR models). Works with no internet, forever.

Internet needed
Never

Needs Google Play services
No

Google code inside
None

Works on
Android 8.0 or newer, ARM phones (virtually all phones)

Pick it if
Your phone has no Google services (for example Huawei or a de-Googled phone), or you want text recognition with no network use at all

Download Usugami-ocr.apk

About internet access: Usugami itself has no internet permission and uploads nothing. The main Usugami.apk needs an internet connection only for text recognition (OCR): the first time you use each language, Google Play services downloads its recognition model (and again if Play services has removed it since). Everything else works offline. If you want text recognition built in, with no download ever, get Usugami-ocr.apk instead. If you don’t need text recognition at all, Usugami-lite.apk is the smallest.

All three editions are signed with the same key. Usugami and Usugami OCR are the same app (package name io.github.nath_goa.usugami), so you can switch between them at any time by installing one over the other; your files and settings are kept. Usugami Lite is an app of its own (io.github.nath_goa.usugami.lite, since version 1.5.1), so it installs next to them. Every release also has a SHA256SUMS.txt file for checking your download.

How Usugami OCR reads text

Usugami OCR has its own text recognition, open source and inside the app: the PaddleOCR PP-OCRv5 mobile models, run on your phone’s processor by Tencent’s ncnn. One model finds the lines of text on each page; then English, French and Spanish are read by PaddleOCR’s Latin-script model, and Hindi by its Devanagari model, which also reads English words. Nothing is downloaded and nothing leaves your phone, so it works in flight mode too. The engine and models are what make Usugami-ocr.apk about 11 MB bigger than Usugami.apk.

It reads printed text best: worksheets, letters, book pages, notices, including photos taken at an angle. Columns are read one after the other.
A page photographed upside down or sideways is read the right way up.
Handwriting, very small or blurred print, tables and maths are read less reliably. A sharp, well-lit photo taken straight on helps the most.
Each page takes a few seconds, longer on older phones. You can cancel at any time.
Its results differ from Google’s text recognition in the main edition: sometimes better, sometimes worse.

GitHub, Obtainium and F-Droid

The same APKs, signed with the same key, wherever you get them, so you can switch between them without reinstalling.

GitHub

Direct downloads of the latest release:

Usugami.apk, about 3 MB
Usugami-lite.apk, about 2.8 MB
Usugami-ocr.apk, about 14 MB

All releases, with what’s new in each, its SHA256SUMS.txt and older versions.

Obtainium

Obtainium is a free app that installs and updates apps straight from their GitHub releases. These links add Usugami to Obtainium with the right file and the signing certificate already set, so Obtainium refuses any APK that wasn’t signed with Usugami’s key:

Open the link on your phone with Obtainium installed, and confirm. Usugami and Usugami OCR share a package name, so add only one of those two; Usugami Lite is an app of its own and can be added next to either. (Added Usugami Lite before version 1.5.1? Remove it and add it again with its link above, which has its new package name.)

On Android 8.0 and 8.1, Obtainium can’t read signing certificates, so it refuses to install an app that has a certificate set. On those versions, add Usugami by hand (below) and leave the certificate field empty.

Adding it by hand

In Obtainium, tap Add app, enter https://github.com/Nath-Goa/usugami as the app source URL, and set:

Filter links by regex: ^Usugami\.apk$ (or ^Usugami-lite\.apk$ for Usugami Lite, ^Usugami-ocr\.apk$ for Usugami OCR)
Expected signing certificate hashes: the SHA-256 fingerprint from Verify your download (leave empty on Android 8.0 and 8.1)

Setting names can differ slightly between Obtainium versions.

F-Droid

Add Usugami’s own F-Droid repository. On your phone, with F-Droid, Droid-ify or Neo Store installed, it takes one tap:

Add to F-Droid

The same button is on nathank.me/usugami, with a QR code to scan. Or add it by hand: in F-Droid, go to Settings → Repositories → + and enter the address. F-Droid checks the fingerprint, so you know the repository is the real one.

Address: https://nathank.me/usugami/fdroid/repo
Fingerprint: 8D92FFB46DB5C052B334438D8E012974D3969A27EACFF4AEEE687B99A4760DA8

Then search for Usugami and install the app you want. Updates arrive like for any other F-Droid app.

It serves Usugami (with the open-source text recognition of Usugami OCR) and Usugami Lite: exactly the APKs published on GitHub, signed with the same key, so you can switch between F-Droid, GitHub and Obtainium without reinstalling.

A listing in the main F-Droid repository is planned; the builds are reproducible for that.

Install

Usugami isn’t on the Play Store, so you install the APK file yourself. It takes about a minute and works on Android 8.0 or newer. Menu names differ a little between phones.

Download. On your phone, open this page and tap Usugami.apk (or Usugami-lite.apk or Usugami-ocr.apk). Your browser may warn that this type of file can harm your device. That’s a general warning for all APK files; tap Download anyway.
Open the file. When the download finishes, tap Open. If you missed it, open the Files app (or My Files on Samsung), go to Downloads and tap the APK.
Allow installing. The first time, Android says something like For your security, your phone currently isn’t allowed to install unknown apps from this source. Tap Settings, turn on Allow from this source, then go back. This permission is per app: it only lets the app you used (for example Chrome or Files) install apps.
Install. Tap Install.
Google Play Protect. Play Protect may say it hasn’t seen this app before, or that it doesn’t recognize the developer, and offer to Scan app. Scanning is safe: it sends details about the app to Google and then lets you install. If Play Protect ever says Usugami is harmful, don’t install it; please open an issue instead.
Optional. Turn Allow from this source off again for that app.

Once it’s installed, Usugami is also in other apps’ Share menu: share images, PDFs, Word, PowerPoint, Excel or EPUB files to it from Files, Photos, a mail app or a chat, and they open in the right tool.

Where is “Install unknown apps”? (Samsung and other phones)

If you skipped step 3 or want to change it later:

Samsung: Settings → Apps → ⋮ (top right) → Special access → Install unknown apps → pick your browser or My Files → Allow from this source.
Pixel and most other phones: Settings → Apps → Special app access → Install unknown apps → pick the app → Allow from this source.
Or search for “unknown apps” in the Settings app.

Updating

Download the new APK and install it over the old one, the same way. Your files and settings are kept. To get updates automatically, use Obtainium.

Switching editions

Install Usugami.apk over Usugami OCR, or Usugami-ocr.apk over Usugami. No need to uninstall first. Usugami Lite is a separate app: install it next to the others, and uninstall the one you no longer want (save any PDFs you need to Downloads first).

Had Usugami Lite 1.5.0?

It was still the same app as Usugami. Since 1.5.1, Usugami Lite has a package name of its own, so Usugami-lite.apk installs as a new app, “Usugami Lite”, next to your old one, which is called “Usugami”. Save any PDFs you need from the old one, then uninstall it. If Obtainium updates it, remove it there and add Usugami Lite again: the old entry can’t update to the new app.

Had Usugami Offline?

Since version 1.5.0 it is Usugami OCR, with open-source text recognition built in instead of Google’s, and there is no Usugami-offline.apk any more. Install Usugami-ocr.apk over it: your files and settings are kept. If Obtainium updates it, change the app’s APK filter there to ^Usugami-ocr\.apk$, or remove it from Obtainium and add Usugami OCR again; until then Obtainium finds no update.

Had PDFer 1.0 or 1.1?

That was Usugami’s old name. Those were private test builds with a different package name, so Usugami installs as a separate app. Install Usugami, then uninstall the old “PDFer”.

“App not installed” or “the package conflicts with an existing package”

A Usugami from somewhere else is installed. Android only updates an app with an APK signed by the same key. If you got Usugami from another site, uninstall it first (save any PDFs you need to Downloads before you do), then install the APK from this page.
You’re installing an older version over a newer one. Android doesn’t allow that; download the latest release.
The download is incomplete or the phone is low on storage. Free some space, download the APK again and try once more.
The old PDFer 1.0 and 1.1 test builds don’t conflict: they have a different package name and install side by side.

Will Android’s new developer verification stop me installing Usugami?

Google has announced that Android will check that apps come from verified developers. As of October 2026 these checks don’t apply to apps downloaded from GitHub, so you can install Usugami as described above. Google has said it plans to extend the checks to all countries in 2027. If that changes how you install Usugami, this page will be updated.

Verify your download

You don’t have to do this, but you can check that an APK really comes from this project. The signing certificate is what matters: Android only installs updates signed with the same certificate, and only the developer has the key.

Package name: io.github.nath_goa.usugami (Usugami and Usugami OCR) or io.github.nath_goa.usugami.lite (Usugami Lite)
Signing certificate SHA-256: 6F:4F:23:AD:E0:3E:63:6A:7C:C3:68:16:89:44:D0:CC:FC:81:32:EF:34:C5:0B:C5:A4:6B:0C:A4:CB:BD:F4:ED

On your phone (Android 9 or newer)

Install AppVerifier, then paste these two lines into it after installing Usugami or Usugami OCR (for Usugami Lite, the first line is io.github.nath_goa.usugami.lite):

io.github.nath_goa.usugami
6F:4F:23:AD:E0:3E:63:6A:7C:C3:68:16:89:44:D0:CC:FC:81:32:EF:34:C5:0B:C5:A4:6B:0C:A4:CB:BD:F4:ED

AppVerifier doesn’t run on Android 8.0 or 8.1; use a computer (below) instead.

On a computer: apksigner, checksums and build provenance

Signing certificate with apksigner from the Android SDK build-tools:

apksigner verify --print-certs Usugami.apk

The certificate SHA-256 digest line must read 6f4f23ade03e636a7cc368168944d0ccfc8132ef34c50bc5a46b0ca4cbbdf4ed. The certificate DN line says CN=Nathan Kumtakar, O=Usugami, but anyone can put any name in a certificate, so only the digest proves who signed the APK. (keytool -printcert -jarfile doesn’t work here: Usugami uses the newer APK signature schemes, which keytool can’t read.)

Checksums: download SHA256SUMS.txt from the same release, put it next to the APK you downloaded and run:

sha256sum -c --ignore-missing SHA256SUMS.txt          # Linux
shasum -a 256 -c --ignore-missing SHA256SUMS.txt      # macOS
Get-FileHash Usugami.apk -Algorithm SHA256            # Windows PowerShell: compare with the file

Your APK must show OK. (SHA256SUMS.txt lists all three editions; --ignore-missing skips the ones you didn’t download.) GitHub also shows each file’s SHA-256 next to it on the release page.

Build provenance: release APKs are built from Usugami’s source by the release workflow on GitHub Actions, which publishes a signed build-provenance attestation for each one. Check it with the GitHub CLI:

gh attestation verify Usugami.apk --repo Nath-Goa/usugami

Source code

Usugami is free and open source, under the GNU General Public License, version 3 or later (GPL-3.0-or-later). Both parts are on GitHub, each with the notices and licenses of the work by other people it includes.

The Android app

Its license includes an additional permission for Google ML Kit, which text recognition uses in the main edition. The APKs on this page are built from this source on GitHub Actions: see build provenance.

This website and the web app

The notices list the libraries, fonts and data the web app includes, such as PDF.js, pdf-lib and Tesseract.js, with their licenses.

Credits

Badge artwork: “Get it on GitHub” from Kunzisoft/Github-badge, badge design by flocke, based on the F-Droid badge artwork (CC BY-SA 3.0), and the Obtainium badge from Obtainium (GPL-3.0). They are not covered by Usugami’s own license.

GitHub and the GitHub logo are trademarks of GitHub, Inc. Obtainium is a project by Imran R. (ImranR98). Neither project endorses Usugami; the badges only link to where Usugami can be downloaded. Usugami is not affiliated with or endorsed by Google, Microsoft, GitHub or Obtainium.