Apple iPhone users have several options when it comes to installing apps on their device. The most common way is to use the App Store, which is available on the home screen. To browse the App Store, tap the icon at the bottom of the screen. You can also search for apps by name, or select a category such as Games or Entertainment.
Another way to install applications that haven't been published in the Apple App Store is to use a program called TestFlight. This is officially approved by Apple and is much more reliable than jailbreaking. Sideloading is another option for adding applications to your iPhone without using the App Store. This process involves downloading an installation file from the internet and installing it directly on your device.
It's not a common way of doing things, but it's possible. TestFlight is a tool for developers to test beta versions of their applications before they are formally released. The airport's goal is to provide app creators with feedback from many evaluators to improve their applications before their launch. If an app has been removed from the App Store, you may still be able to access it.
Web applications are sometimes an option if you need to access applications that aren't in the official Google store. Jailbreaking your phone removes certain controls and allows you to install applications that aren't available on the App Store, among other things. Cydia is packed with free and paid apps that aren't in the Apple App Store and allow you to do all kinds of interesting things. Apple also allows developers to load applications to their iPhone from Xcode, a software for creating applications for iPhone, so that they can test current applications or show their creations to friends and family.
Be aware that jailbreaking your phone can be risky and you should only install apps outside of your phone's app store if you have a very good reason to do so. You can also install applications from file synchronization services, such as Dropbox, as long as you enable this feature for the corresponding application. Learning how to manually install apps on your iPhone will teach you an additional way to install applications if you can't do it through the app store app on your iPhone. With this knowledge, you'll be able to access apps that may have been removed from the App Store or find alternative ways of downloading them.