File extension .sis

If you try to download a file that ends with .SIS you will find out that there is nothing you can use to open the file as it is an executable file for the Smybian operating system that is typically used on phones these days.
It's designed to be put on the phone and run there.
For example it is a file to be used on your cell phone allowing you to have a caller ID.
In order to install a SIS file on a compatible phone, you will need to transfer the file to the phone using the phone's PC communication software.
Then you will need to open the SIS file on the phone to run the installer.
The file extension sis means literally: Symbian installation source.
As the name says the file extension sis is an installation file for Symbian OS.
It is the OS you find for example in Palm PDAs and Nokia, Ericsson, and Motorola phones.
Incorrect associations are the cause of many file extension errors.
In a few words: the file extension sis is associated with software, themes, applications and games which can run in symbian operating system. Usually Symbian OS is found in mobile devices.