What is the difference between unsigned and signed mobile phone software?

You can use some unsigned software. .

But most software needs to be signed. . .

Signature is to ensure the security protection of the installed software by the mobile phone system. .

5800 is S60 5 version. . . You'd better apply for a mobile phone certificate. . Then download any software before using it. . You can use it.

Or crack the phone by cracking. . Then you can install it without signing software in the future. . .

Let's call it a day. . Thank you for your cooperation!