Installing apps on many platforms requires going to a specific store app or web site. Apple has the App Store, Android the Play Store, and the Meta Quest 2 has the Oculus Store. Unlike with Windows and MacOS, you can’t download a Quest app from any web site and install it. This is good in that it makes it more difficult for people to install malicious software (although it’s not foolproof). It also ensures that apps are written in a correct way that won’t interfere with other apps on your device.
The problem with these app stores is they tend to have lots of rules for what they accept. Sometimes, apps will be rejected, and the developer won’t even fully understand why. It can be a frustrating process for small developers to navigate the process, and less polished apps may never make it.
Remember when I said you can’t download apps from random web sites? Technically, I lied. You can do it, but it’s nowhere near as convenient as using the official store. Sideloading generally requires some additional steps that can be intimidating to some users. Apps that are sideloaded on the Quest 2 are also demoted by not showing up in your default app list in VR. Instead, you need to change a filter to see apps from Other Sources. These steps make it unlikely that an app will be installed by many via sideloading.
For most platforms, including the Quest 2, you’ll need to register as a developer to enable sideloading at all. This is because the feature itself is designed so developers can test their apps before submitting them to the store. Fortunately, it doesn’t cost anything to enable this. You’ll need to visit the Oculus Developer site and register a new organization, then you can unlock your device.
To simplify the process, I recommend using SideQuest. This is a web site of independent apps that can be sideloaded. They also provide a great tool for Windows, MacOS, and even for the Quest itself so you can find and install these unofficial apps with ease. Their downloads and some awesome how-to videos are available on their Get SideQuest page.