If you thought Google Nexus S can only read the NFC [Near Field Communication] tags, there is a surprise in store for you. Few developers in Argentina discovered hidden API calls in Gingerbread, that includes writing NFC tags, and Nexus S is capable of writing them.
“We’ve been analyzing the Android kernel source code and we found a lot of ‘@hide’ tags in the NFC java classes,” says Gustavo Gonzalez from the groups of developers behind the discovery. “The @hide tag is used to mark public APIs that are not to be exported in the SDK. This is used by the Android team to have APIs accessible across packages without having them available to applications. APIs marked with @hide are considered private to the Android platform and can change at any time, so you cannot rely on them.”