Zoiper is very much alive, working harder than ever.
This community forum is for users to help each other. We do not have the resources to help every free user. (although we do try to answer some questions when we have some time)
Soon a new version for desktop (full rewrite) will be released. you can participate in the beta on http://www.zoiper.com/labs
The new version of zoiper for android can be tested here:
https://play.google.com/store/apps/details?id=com.zoiper.android.zoiperbeta.app&hl=en
A new version for iOS is also in the making but no public beta is available yet.