Demons usually do not keep time (like Trial software) but performance is limited. In some cases, all operations are disabled until a license is purchased. Short programs have limited performance free, but charge a higher set of features or for removal of ads from program organizations. In some cases, ads may be displayed to users.
Basically, the product is offered Free to Play (Freemium) and the user can decide if you want to pay a fee (Premium) for other features, services, tangible or virtual goods that increase game performance. This license is commonly used for video games as well allows users to download and play the game for free.
