AT&T has set a date for switching off its 3G WCDMA network. Starting February 2022, customers will need a 4G phone with VoLTE technology (a feature AT&T refers to as HD Voice) to connect to AT&T's network. Most smartphones released since 2014 support this technology, as well as most feature phones released in the last two-three years. Phones that will stop working include the Apple iPhone 5s and older, Samsung Galaxy S4 and older, the original Google Pixel, and the OnePlus 6T and older. Shutting down the 3G network will allow AT&T to allocate all of its airwaves to more-efficient 4G and 5G technologies, enabling greater network capacity and data speeds for 4G and 5G customers. AT&T sent an email to some customers earlier this week saying they needed to upgrade their phone without making clear the 2022 deadline. AT&T issued the following statement about the email: "This email was one of many planned to keep customers informed about the shutdown of our 3G network in early 2022. It should have included the date that certain devices would no longer be supported. We apologize for any confusion this may have caused and will be more clear in future updates."