This volume has been conceived as a follow-up to the first Special Issue of the MDPI journal Mathematics to illustrate and show how one may utilize the applications of differential equations in a multitude of fields; it also encompasses the latest trends in applied mathematics research. The Editors’ choice is driven by the awareness of mathematical modeling’s growing importance in all scientific areas. All the articles that have been submitted for publication are original and will prove to be valuable and interesting for the readers. Moreover, they will certainly show an appreciation for the heterogeneity of the 11 papers included in this reprint and will discover how helpful differential equations are in a wide range of disciplines. Additionally, we are confident that reading this reprint will be inspirational for young scholars.