How to Install an APK

This guide explains how to install an APK file from 1234app on an Android phone or tablet safely, including how to check that the file is genuine and how to fix the most common problems.

What is an APK?

An APK (Android Package) is the file format Android uses to install apps. When you install an app from Google Play, your phone also downloads and installs an APK; it just happens automatically.

On 1234app, every APK is added by our team, checked before it goes live, and shown with its SHA-256 checksum, signing certificate and the permissions the app requests.

Before you start

• Android version. The app page lists the minimum Android version. Check yours under Settings > About phone.
• Storage space. Keep at least twice the file size free, because Android needs extra room while it installs.
• Battery. Make sure the battery is charged or the phone is plugged in so the install isn’t interrupted.
• Permissions. Read the permission list on the app page. If a simple app asks for access that doesn’t make sense, don’t install it.

Android 8.0 and newer

Since Android 8.0 (Oreo), permission to install apps from outside the Play Store is granted per app, for example only for the browser or file manager you use.

1. Open the app’s page on 1234app and tap Download. Wait for the download to finish.
2. Open the download notification, or open the APK from your Files or Downloads app.
3. If a warning says your phone isn’t allowed to install apps from this source, tap Settings.
4. Turn on Allow from this source (Install unknown apps) for that browser or file manager, then go back.
5. Tap Install and wait for it to finish. Then tap Open or Done.

Android 7.1 and older

On older versions the setting applies to the whole device instead of a single app.

1. Go to Settings > Security (on some phones: Settings > Lock screen and security).
2. Turn on Unknown sources and accept the warning.
3. Download the APK from the app’s page on 1234app and open the file.
4. Tap Install and wait for it to finish.
5. Go back to Settings > Security and turn Unknown sources off again.

Checking the SHA-256 checksum (optional)

A checksum is a fingerprint of the file. If the checksum of the file on your device matches the one on the app page exactly, the file is identical to the one published on 1234app and wasn’t changed on the way.

1. Copy the SHA-256 value from the app’s page on 1234app.
2. Calculate the checksum of the downloaded file. On Android, use a file manager or hash checker app that shows SHA-256. On a computer, run certutil -hashfile file-name.apk SHA256 (Windows) or shasum -a 256 file-name.apk (macOS/Linux).
3. Compare the two values. If even one character differs, the files aren’t the same: delete it and download it again from 1234app.

Updating an app

To update, download the latest version and install it over the old one. Your data is kept.

Android only accepts an update signed with the same certificate as the installed app. On 1234app, package names and signing certificates are pinned from the first version, and a version with a different certificate is flagged and held for review by our team.

If the app on your phone came from another source with a different certificate, the update will fail. Back up your data, uninstall the old app, then install the version from 1234app.

Troubleshooting

“App not installed”

Usually caused by low storage, an incomplete download, or an existing version signed with a different certificate. Free up space, download again, or uninstall the old version first.

“There was a problem parsing the package”

The file may be damaged or incomplete, or your Android version is lower than the app’s minimum. Download it again, compare the checksum, and check the minimum Android version on the app page.

“Package conflicts with an existing package”

Your device already has an app with the same package name but a different signing certificate. Uninstall the old app, then install again.

Google Play Protect warning

Play Protect may show a warning for apps that weren’t installed from the Play Store. Read it carefully. If it says the app is harmful, stop, and report it with the Report this app button on the app page.

Not enough storage

Delete files or apps you don’t use, clear caches, and try again. Once an app is installed, you can delete its APK from your Downloads folder.

Safety tips

• Only download from the official download button on the 1234app app page, not from ad links or other sites.
• When you’re done installing, turn Install unknown apps or Unknown sources off again.
• Pay attention to the permissions an app asks for when you first open it, and deny the ones it doesn’t need.
• Our checks lower the risk, but no check is perfect. The app page shows whether the file was virus-scanned. If an app behaves suspiciously, uninstall it and report it.