Nokia's mobile phone uses Symbian system. Aiming at the virus problem in the second edition of Symbian system, Nokia has adopted a rights protection mechanism for mobile phones since the third edition of Symbian, which is called software signature.

Software signature is to authorize it, such as: connecting to the network, sending messages, reading mobile phone information, automatically starting and running, reading and writing data to mobile phone memory or memory card, and so on.

Software signature is beneficial to protect mobile phone, its privacy, security and the stability of mobile phone system. For example, avoid automatic message deduction of malicious software, avoid mobile phone data leakage and so on.

You can search for "free application for Saipan card" on the website. Generally, you can make a proof of your own mobile phone within 24 hours. It needs the IMEI of your mobile phone, which is the serial number displayed in *#06#.

At the same time, you can directly install the "Saipan Direct Sign Tool" without having to apply for a certificate. This software is completely free to use. After the installation, other software can be signed without cracking the system. However, the software needs to be connected to the network. Signing a software requires 0. 1K traffic, which is very small, and the signing process is very fast, and it can be done within one minute.