Google Wallet will require Android users to run KitKat, the latest version of the Android operating system, to use the wallet's contactless payments feature as of April 14, according to a post on the Google Wallet support site.
KitKat, or Android 4.4, introduced Host Card Emulation (HCE), a technology that enables contactless Near Field Communication transactions without the need for accessing the phone's secure element. This allowed Google Wallet to be used for contactless payments across all mobile carriers.
Google has been notifying Google Wallet users of the change by email, according to the tech news site Droid Life.
The requirement of KitKat suggests that Google is planning to support contactless payments only for devices that can use HCE as an alternative to accessing the phone's secure element. The change "is a bit of a downer," says Droid Life, which notes that only 2.5% of Android devices run KitKat.
HCE has drawn a strong following since Google enabled the feature. Visa and MasterCard are also supporting the technology, while several banks worldwide are also adopters. Isis, a venture of AT&T, Verizon Wireless and T-Mobile USA, has said it could use HCE for non-sensitive data while using the secure element for information that requires more security.
The KitKat mandate is the latest change for Google Wallet, which has undergone many updates over the past couple of years.