Allowing unknown sources: APK installs on Android

A casino app that does not come from Google Play can only be installed on Android once the system allows the installation of unknown apps. Android blocks such installs until the user agrees, and that consent has to be given before the download and installation. The full order of download, permission, installation and update is covered in the guide on how to install a casino app.

Depending on the Android version, the setting has a different name: from Android 8.0 you grant the permission per app, up to Android 7.1.1 there is a global switch called “Unknown sources”. Of the four casinos covered here, only 22Bet and Irwin name an Android app to download, while Frumzi and 5Gringos run in the mobile browser without any installation.

What the setting does

The setting decides whether an app is allowed to put other apps on the device. Installs from Google Play need no permission; Android only blocks apps from other sources. When you download an APK in the browser and tap it, the file is handed to the system's package installer. If the browser lacks the permission, the process ends at that point, before the app ever lands on the device.

You do not need a separate “APK installer” from the internet for this. In one forum the answer to exactly this question is short: “Du brauchst aber auch keinen eigenen APK Installer” (you don't need your own APK installer). Android ships with the tool for installing, and the permission applies to the app you open the file from, not to the file itself.

Why casino apps take this route at all has to do with Google Play. For Germany, Google Play only allows sports betting, horse racing and lotteries as gambling apps; online casino games and virtual slot machines are missing from the list. Developers may instead host APK files on their own website, provided users agree to the installation of unknown apps. Source, file size and Android version of individual operators' packages are summarised in the overview of the casino app for Android.

On the iPhone there is no comparable setting, because iOS does not install APK files. There, the route goes through the App Store or the mobile website. For 22Bet the information differs: according to goal.com the app is in the App Store, while a search via the iTunes interface for Germany on 08.10.2026 found no entry. What this means for Apple devices is described on the page about 22Bet on iPhone with the App Store, the mobile site and both source positions.

Android 8 and newer: permission per app

Since Android 8.0 (API level 26) you no longer grant the permission globally, but per source on the system screen “Install unknown apps”. It lists the apps that can open files, such as Chrome, another browser or the file manager. Each of these apps has its own switch, and only the app that has been allowed may hand packages to the installer.

This applies unchanged to the versions people search for most: Android 11, 13, 14, 15 and 16 all follow the model introduced with Android 8.0. Samsung devices also work with the per-app permission; where the screen sits in the menu differs by manufacturer and version. The quickest way to the right entry is the search function in the settings with the term “unknown apps”.

Only allow the app you actually open the file with. If you download the APK in Chrome and tap it in the download bar, Chrome needs the permission. If you open the same file later from the download folder via the file manager, the file manager needs it. A permission for a third app does not help at that moment.

For 22Bet the route has three steps: load the APK on the official site, allow “Unknown sources”, then tap the APK and install it. The term “Unknown sources” comes from older Android versions; on current devices it corresponds to the permission for the browser the file was downloaded with. All data on the 22Bet app with Android, iOS and push notifications is collected on the brand page.

There is a separate guide for the download itself: the page on the 22Bet APK for Android describes source, file size and installation for this one package only. For Irwin, the only statement is that the app for Android is available for download; the casino points to the download icons at the bottom of the home page. Whether there is an APK behind them that needs this permission is not stated by any source.

Android 7 and older: global setting

On devices with Android 7.1.1 (API level 25) and older there is the global setting “Unknown sources” under Settings › Security. The tick applies to all apps at once: once it is set, every app may install packages, not just the browser. An advisor in a forum puts it like this: “du musst unter Einstellungen-->Sicherheit das Häkchen bei Unbekannte Herkunft setzen” (tick “unknown origin” under Settings › Security).

Android recommends allowing only the individual app instead of the global setting whenever the device offers that choice. The global tick stays active until you remove it again; every file loaded later from any app then goes into the installer without a new permission.

The older generation matters for casino APKs because the packages' requirements differ. For the 22Bet APK, goal.com names Android 6.0 or newer, while Uptodown states “Requires Android 7.0 or higher”.

Switch greyed out?

A greyed-out switch is the most frequent question about this setting. A user with a Pixel 6 writes that the installation needs “eine Berechtigung die deaktiviert ist” (a permission that is disabled) and that the switch cannot be moved. The first answer in the forum reads: “Vielleicht hast du Family Link oder irgendeinen Kindersicherung. Die blockiert das.” (Maybe you have Family Link or some parental control. It blocks this.)

Family Link and other parental controls block the installation of unknown apps for the managed account. Google requires approved gambling apps to exclude minors technically.

A second cause lies with the mobile carrier. Some network operators do not allow installation from unknown sources, so the option stays locked even without parental controls. In that case, casino offers remain available in the mobile browser.

Not every failed installation has to do with the permission. One forum advisor writes: “An dem Erlauben der unbekannten Quellen wird es nicht liegen” (it won't be down to allowing unknown sources). If the permission is missing, Android explicitly reports the blocked installation; other messages point to other causes. Another advisor names three: the phone is not compatible, the APK is corrupted, or unknown sources are not allowed.

Google Play Protect can also stop an installation, regardless of the permission. It is switched on by default, checks apps during installation, including those from other sources, and can block known harmful apps. Google recommends always keeping Play Protect switched on.

Taking the permission back after installation

Once the app is installed, the permission is no longer needed. From Android 8.0 you switch the source off again on the “Install unknown apps” screen, for example for Chrome; the app already installed is not affected and keeps running. Up to Android 7.1.1 you remove the global tick again.

Updates work the same way as the first installation: a new APK needs the permission again. If you took it back after installing, switch it on briefly for the update and off again afterwards.

Google warns that apps from unknown sources can put the device and personal data at risk, up to damage, data loss and theft. When installing from other sources, the device may also send information such as app URLs, device ID, Android version and IP address to Google. One piece of forum advice sums up the responsibility: whoever enables “Programme aus unsicheren Quellen zulassen” (allow programs from unsafe sources) carries the risk of a harmful file themselves.

From Android 13 a further block applies: during installation, sensitive settings such as accessibility can be restricted for the new app. They can only be released via “Allow restricted settings” in the app info, and Google advises against it unless you trust the developer.

How to recognise a genuine file, what role origin and file size play and what a Play Protect warning means is covered in detail on the page about casino APK safety with all the checking steps.