Before Windows Phone 8.1 update 1 ( GDR1) it would just allow to initiate calls or control playing music. But after GDR1 update, it now supports “asking questions” and one can strike normal owner to Cortana conversations.
In case you are worried about someone misusing this Cortana feature to steal you data or breach your privacy, you can disable it by going to Settings——> Speech—–>Uncheck, use speech when phone is locked. Check the screenshot above.
You can read all the Windows Phone 8.1 update 1 ( GDR1 ) details in one place on our dedicated Windows Phone 8.1 GDR1 page. Also check our hands-on demo video.