
For users of older iOS devices that don’t support the latest firmware from Apple, the App Store will now allow you to install the latest-compatible versions of applications where the latest versions of the applications require a firmware too new for your iOS device to run.
For example, if a developer chose to only support iOS 7.0 and later in the latest version of one of their applications, and you were stuck with a device such as the iPod touch 4G, where iOS 6.1.3 is the latest firmware you can run, the App Store would allow you to download the latest-compatible version of that application that was out before the iOS 7-only version of the application was released, so you could run it.
Should you fall into this inconvenient situation, you would get an alert like the one above that lets you know that you have the option to download an earlier version of the application that supports your current firmware. You will be able to cancel downloading the application, or choose to download the earlier version of the application that supports for your earlier firmware.
There are some downsides to downloading earlier versions of applications in the App Store. For example, developers may no longer support these versions of applications, so if you experience bugs, you’re kind of stuck with them. In addition, you won’t get all of the features that may be available in the latest version of the application.
On the other hand, the new App Store feature does allow legacy devices to at least have multiple options instead of not being able to install applications made for newer iOS firmware versions altogether.
Sources: AppleInsider
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