You need a Symbian certificate, that is, a mobile phone certificate, which can be understood as a software pass. The English name is Phone Certificate. Symbian S60 has greatly improved its security, and has stricter regulations on the third-party software installed and running in the system. Special restrictions are imposed on the operation of some software related to mobile phone hardware and software/personal information security (for example, automatic startup of mobile phone startup is one of the restricted functions).

A mobile phone serial number can be used for registration.

What can't be installed has no certificate, and can only be installed after signing. The certificate can be downloaded from Saipan Forum.

The software that can be installed is certified by Saipan, and can be installed even without signing.