Unstructured Supplementary Service Data (USSD), sometimes referred to as "quick codes" or "feature codes", is a communications protocol used by GSM cellular telephones to communicate with the mobile network operator's computers.

USSD is a fundamental service that all GSM network operators support to enable the exchange of menus (or strings) between a subscriber and an operator. The acronym USSD stands for Unstructured Supplementary Service Data. It does not require the device to be connected to the internet, which enables it to function on even the most basic phones.

2025年1月17日 · In this article, we’ll jot down a comprehensive list of Android secret codes and USSD codes that you can use to access a range of back-end settings, hidden features, and information on your Android smartphone or tablet from brands like Samsung, OnePlus, Xiaomi, Vivo, Realme, Oppo, Nokia, etc.

2022年8月14日 · You can access the hidden functions on your smartphone via the so-called USSD or GSM codes. Using a short string of numbers and characters, you can, for example, display your own phone number, set up call forwarding or check your prepaid balance.

USSD is a kind of protocol (Supplementary Service protocol) that is designed for a UE to communicate with the service provider's computer. It was originally designed for GSM cellular communication and now is being used in WCDMA network as well.

2024年7月18日 · USSD，全称为Unstructured Supplementary Service Data，是一种基于GPRS的无线通信服务数据协议。 以下是关于USSD的. 1. 基本定义： USSD是一种用于在移动设备与通信网络之间进行数据交互的协议。 它提供了一种快速、高效的方式来访问和提供移动网络服务。 该协议不依赖于特定的应用程序或操作系统，因此在不同的手机和设备上都能实现相似的功能。 2. 特点： USSD协议的主要特点是其非结构化特性，这意味着它并不依赖于固定的数据格式或特定 …

2024年6月17日 · USSD is a convenient way for network configuration of a mobile phone. It also offers the user a menu of service options from which they can request account balance, buy airtime, or accomplish any other simple task easily from the comfort of their home or office.

2025年3月3日 · Android devices come equipped with a variety of secret codes—also known as USSD (Unstructured Supplementary Service Data) or MMI (Man-Machine Interface) codes—that allow users to access hidden features, perform diagnostics, and retrieve information. ... *#9900# – Enter system dump mode. ...

Learn what standard USSD codes are and their crucial role in mobile communications. Discover how they differ from custom or dedicated USSD codes. Explore the advantages and applications of standard USSD codes across various sectors. Gain insight into the technical and operational aspects of using USSD codes.

2024年12月12日 · USSD codes, or Unstructured Supplementary Service Data codes, are a form of communication protocol used by mobile phones to interact directly with their network operator. These codes, usually starting with an asterisk (*) and ending with a hash (#), are typed into your phone’s dialer and executed by pressing the call button.