Apple’s iOS 11 will not support slow and old apps that use a technology called 32-bit, rendering those programs useless. Additionally, Apple will not allow users to find 32-bit apps in its App Store, effectively killing them off until the app developers update their older apps to support the new 64-bit process, which speeds up apps and makes them more usable on newer iPhones and iPads.

When users download iOS 11, they’ll get a notification from the operating system, saying that a particular app “needs to be updated.” Apple’s notification says that the app “will not work with iOS 11” and it will be banned from use until it’s updated.

Apple (AAPL) started to use 64-bit apps in 2013 after the company launched the iPhone 5S, the first smartphone from the company to come with a 64-bit processor. At that time, Apple pressured developers to start taking advantage of the faster chip technology, but still allowed 32-bit apps to be developed and brought to its App Store. In 2015, however, Apple announced that all new apps and updates would need to run on 64-bit.

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While the majority of app developers heeded Apple’s warning and updated their programs, there are still some that have not, which means they haven’t been updated in over two years.

Apple announced last year that it would start to inform users of older and outdated apps, and this year, decided to finally stop supporting the older programs. Since last year, users have only been informed that their older apps would “slow down” their devices but Apple would allow them to be used. Now, though, Apple has seen enough and is stopping them in their tracks.

Apple’s iOS 11 will be available for download starting today. The software is free and users will get a notification on their iPhones and iPads when it’s ready to be downloaded.