**Preface to "Internet and Smartphone Use-Related Addiction Health Problems: Treatment, Education and Research"**

A Special Issue on health and educational effects due to problematic Internet and smartphone use has been tackled in the International Journal of Environmental Research and Public Health (IJERPH) titled: "Internet and Mobile Phone Addiction: Health and Educational Effects", developed from 2019–2020. It is the second edition of the previous Special Issue "Internet and Mobile Phone Addiction: Health and Educational Effects", which was developed between 2017 and 2018. The recognition of these Internet use-related addiction problems is now formal, after one of these problems became accredited by the public health organization, World Health Organization (i.e., gaming disorder). However, the debates continue, and the research is quite prolific. For detailed information on the Special Issue referred to, you can visit https://www.mdpi.com/journal/ijerph/ special issues/Internet Smartphone Addiction. This Special Issue presents some of the main emerging research on technological topics on health and education approaches to Internet use-related problems, before and during the beginning of coronavirus disease 2019 (COVID-19). The objective is to provide an overview to facilitate a comprehensive and practical approach to these new trends to promote research, interventions, education, and prevention. It contains 40 papers, four reviews and thirty-five empirical papers and an editorial introducing everything in a rapid review format. Overall, the empirical ones are relational, associated with specific behavioral addictive problems with individual factors, and a few with contextual factors, generally in adult populations. Many have adapted scales to measure these problems, and a few cover experiments and mixed methods studies. The reviews tend to be about the concepts and measures of these problems, intervention options, and prevention. The Special Issue covers the following Internet use-related addiction problems: Internet addiction or problematic Internet use, smartphone addiction or problematic mobile phone use, and other specific problems, such as (video) gaming disorder, social media addiction or Facebook addiction, cybersex addiction or problematic usage of pornography, online gambling or eGambling, buying addiction or problematic Internet shopping, among other related behavioral and excessive problems. In summary, it seems that these are a global culture trend impacting health and educational domains. Internet use-related addiction problems have emerged in almost all societies, and strategies to cope with them are under development to offer solutions to these contemporary challenges, especially during the pandemic situation that has highlighted the global health problems that we have and how to holistically tackle them.

> **Olatz Lopez-Fernandez** *Editor*
