"Bioengineering & Translational Medicine is a peer-reviewed, online, open access journal focused on the fundamental ways chemical and biological engineering approaches drive and provide innovative technologies and solutions that impact clinical practice and/or commercial healthcare products" (AIChE). Available for iOS or Android.
"ChemistryOpen is a multidisciplinary, gold-road open-access, international forum for the publication of outstanding Reviews, Full Papers, and Communications from all areas of chemistry and related fields" (ChemistryOpen). Available for iOS or Android.
"FEBS Open Bio is an online-only open access journal for the rapid publication of research articles in molecular and cellular life sciences in both health and disease. The journal's peer review process focuses on the technical soundness of papers, leaving the assessment of their impact and importance to the scientific community" (FEBS Open Bio). Available for Android. Download FEBS Press for iOS.
Arxiv eXplorer is an Android mobile app for Arxiv.org - "arXiv is a free distribution service and an open-access archive for 1,823,661 scholarly articles in the fields of physics, mathematics, computer science, quantitative biology, quantitative finance, statistics, electrical engineering and systems science, and economics. Materials on this site are not peer-reviewed by arXiv" (arXiv.org). Available for Android only.