sis distribution

[bart12]

Hello,

I really need your help. I am about to publish a Symbian 9.3 application. The application is intended to be available by WAP and it will work 6 months (counter is implemented inside the application). The sis file is published with x-epoc/x-sisx-app MIME type.

However, I find a problem that after browsing to URL of the application, the application is downloaded to C:/Data/downloads or E:/Data/downloads and then installed. After installation, the installation sis file remains in one of these directories. It is visible from file manager and any user can reinstall the application so that counter will be reset. The user can even copy the sis file to the computer by Nokia PC Suite and install on another phone. Is it possible to delete sis file after installation or how else should I publish the application?

[wizard_hu_]

There is no way to provide reliable protection (including time-limited demos, trials) on the device against tampering attempts of a power user. Against a simple user, you can look around on the device when your application starts (perhaps only the first time), and remove your own installer file.
Nowadays it is not a highly discussed topic, but you can find many threads from 1-2 years ago, if you search for demo, trial. The only reliable way is to provide a centralized registration/activation server, and contact it from your application occasionally. On 'server', I mean a server on the Internet.

[bart12]

Thanks,

Implemented counter is reliable for me. However, the problem I see is the fact that users can find sis file using file manager and reinstall or even copy it to the computer (the latter is also dangerous while publishing full applications). Can DRM or any other mechanism protect files so that sis can be installed only once and not allowed to be copied?

[wizard_hu_]

Implemented counter is reliable for me.

However, the problem I see is the fact that users can find sis file using file manager and reinstall or even copy it to the computer (the latter is also dangerous while publishing full applications).

Is it only me who sees a controversy here? "It is reliable" vs. "However, the problem"

Can DRM or any other mechanism protect files so that sis can be installed only once and not allowed to be copied?

Technically there is playcount feature in DRM, even there is/was a known issue with it (http://wiki.forum.nokia.com/index.ph...layback_rights), but I do not know if it can be applied to an installer file (probably yes, since files from Ovi are said to come with DRM forward lock). Copying is still going to be possible, however that will not really matter if the license manager blocks further installation attempts.