Text messaging has long been a popular activity, and today smartphone apps enable users to choose from a plethora of mobile messaging applications. While we know a lot about SMS practices, we know less about practices of messaging applications. In this paper, we take a first step to explore one ubiquitous aspect of mobile messaging -- messaging history. We designed, built, and trialled a mobile messaging application without history named forget-me-not. The two-week trial showed that history-less messaging no longer supports chit-chat as seen in e.g. WhatsApp, but is still considered conversational and more 'engaging'. Participants expressed being lenient and relaxed about what they wrote. Removing the history allowed us to gain insights into what uses history has in other mobile messaging applications, such as planning events, allowing for distractions, and maintaining multiple conversation threads.

Foralphages1, the new Vajda-type information measureJalpha(X) is a quantity generalizing Fisher's information (FI), to which it is reduced foralpha=2. In this paper, a corresponding generalized entropy powerNalpha(X) is introduced, and the inequalityNalpha(X)Jalpha(X) gesnis proved, which is reduced to the well-known inequality of Stam foralpha=2. The cases of equality are also determined. Furthermore, the Blachman-Stam inequality for the FI of convolutions is generalized for the Vajda informationJalpha(X) and both families of results in the context of measure of information are discussed. That is, logarithmic Sobolev inequalities (LSIs) are written in terms of new more general entropy-type information measure, and therefore, new information inequalities are arisen. This generalization for special cases yields to the well known information measures and relative bounds.