On the License screen (see Figure 1), you can purchase or activate a paid license, or you can get a demo license.
To open the License screen, do one of the following:
•In Dr.Web versions that require a license for all the components to function:
▫Tap More in the notification about a missing license on the main screen of Dr.Web.
▫On the Dr.Web main screen, tap Menu 
and select License.
•In Dr.Web versions that require a license for some of the components to function:
▫On the application main screen, select one of the components that require the purchase of a license.
▫On the Dr.Web main screen, tap Menu and select License.
Figure 1. License screen