The topic of unsigned applications was introduced in my previous post and I need to elaborate a little further. There is another way to install unsigned applications that doesn’t involve hacking the N8’s firmware. The process involves signing the application with a developer certificate. Developers obtain this type of certificate from Symbian Signed, allowing them to deploy applications for testing purposes, to a limited audience. Applications signed with a developer certificate are only installable on the device for which the certificate was granted (based on the IMEI number).
How does a typical Nokia N8 owner obtain a developer certificate? The answer is to visit this website and follow the instructions. OPDA is a Chinese website that issues developer certificates with 17 capabilities. Once you have obtained a developer certificate restricted to your phone, you can now sign any previously unsigned application and install it. I prefer using SisContents to sign the application on the PC, then installing it with PC Suite. It is very important that you don’t lose your .cer and .key files received from OPDA (e-mail both files to your e-mail account as a backup).
I explained in a previous post that the Symbian operating system is divided into 21 parts, one of which is open and 20 are behind various capabilities, based on how sensitive they are and which phone functions they protect. Hence, a developer certificate grants the application access to 17 of the 2o capabilities. Three of the 2o capabilities are very strictly controlled and can only be granted by the device manufacturer directly. They allow access to the /sys and /resource folders on the C: drive and the ability to modify DRM-protected content.
This means that the application you sign and install can access most of your phone’s functions (such as USB, Bluetooth, audio, video, camera, WLAN, GPRS, phone dialer, text messages, contacts, internal GPS, external GPS, running processes, phone status and system settings). What this means is you need to be very careful which application you sign and then install. If you download an application containing malware, then sign and install it, there may be unfavorable consequences when the application is run.