AltStore is an alternate version of the App Store that does not require jailbreak.
After a while without receiving much attention, the practice of jailbreak has recently turned around again, including support for iOS 12 (then Apple's latest operating system). Still, the adoption of users is not the same as years ago, mainly because it involves a sometimes risky process.
But what if you no longer needed jailbreak to have access to some features (or in this case also games) that are generally excluded from the App Store? This is precisely the proposal of the Altstore, an alternate version of Ma's store created by developer Riley Testut.
In fact, the software is something like a ?mini App Store?, with some classic console games like super Mario; however, perhaps AltStore's most popular feature is the built-in game emulator, which supports some of the games offered by the software.
According to Testut, AltStore uses Apple's ability for developers to test their apps on real devices, rather than corporate certificates that may be dropped by Ma (as we have seen with Facebook and Google). In short, the tool basically makes the device think that it is installing applications you created for internal testing.
Because these applications should theoretically be installed on Xcode, AltStore simulates this process from a complementary application made for macOS and Windows. Users can explore and install apps directly on iPhones and iPads, but this requires the desktop version to run in the background to work.
To do this, you must first download and install AltServer (AltStore server) on your computer. Then launch the app and connect your iPhone or iPad to your computer with a USB cable by selecting your device from the app menu.
During the installation process, you will be prompted for your credentials (Apple ID) to obtain a developer certificate. If you are uncomfortable sharing your account data, you can create an alternate Apple ID to test the feature.
After installation, the AltStore app will appear on your iPhone (or iPad) Home screen, just like any other app. The app store itself is very similar to the App Store, with the same design base and some similar options.
According to the developer, even more apps will be available from AltStore after its official release tomorrow, September 28th. He also points out that any other developer can participate in the open source project available on GitHub.