A Nanosite is a downloadable offline mini-website tailored for mobile phones using both J2ME and .NET.

Nanosites have become popular amongst companies that want to use another media for corporate branding.

A Nanosite can be easily downloaded to a mobile handset via WAP, GPRS, Wi-Fi or Bluetooth.

Additionally, nanosite or nano-site has been used to refer to interactive rich media ads that bring some of a website's content and functionality into the ad unit.