The third edition of S60 has greatly improved the security, and has stricter regulations on the third-party software installed and running in the system. Some operations involving mobile phone software and hardware security/personal information security are particularly restricted (for example, automatic startup of mobile phone startup is one of the restricted functions). In order to realize these "specially restricted" functions, the application must obtain a "signature". In other words, someone should be responsible for the safety of this operation! A program without any signature cannot be installed and run.

When we say signature, we generally mean the user's personal signature:

Strictly speaking, this should belong to the "developer signature". Because Symbian provides a kind of "development certificate" for software developers, the original intention is to let software developers do software testing. This "development certificate" is associated with the IMEI code of the machine used for testing. The software signed with this certificate can only be used on the machine corresponding to the IMEI code, not on other machines. Our so-called "self-signature" is actually in this way. To put it bluntly, you said you were developing software, you provided the IMEI code of your tester, and Symbian issued you a "development certificate". You use this certificate to sign your Test Software. You are responsible for your "development behavior"! That's all. In addition, the development certificate is valid for half a year from the date of issuance, but within the validity period of the certificate, there is no limit on the use time after the program is signed and installed.

Imei = international mobile equipment identity = international mobile equipment identity card. This is similar to your "resident ID card". This thing belongs to the privacy scope. Symbian will not directly input this information on the website to protect users' privacy.