Definition - What does Nagware mean?
Nagware is a software utility that "nags" users into upgrading or buying a premium version of software by sending constant pop-up messages or notifications. Software developers use nagware as a marketing tactic to remind users to take advantage of special offers and purchase software.
Nagware is also known an begware, annoyware, nagscreen and guiltware.
Techopedia explains Nagware
Generally part of a freeware or software utility, nagware works according to a predefined time or event set in the software. For example, after the nagware's trial edition date has passed, users are continuously reminded to buy or upgrade the software and/or license. The pop-up, or nagscreen, displays when the user opens the software or starts the system - or cyclically after a predefined period. To avoid nagware, a user must ultimately buy, upgrade or completely uninstall the software.