App: Elements of Matter
Developer: Ventura Educational Systems
Genres: Bildung, Nachschlagewerke

Elements - Periodic Table Reference for iPhone, iPad and Apple Watch provides detailed information on all the elements in the Periodic Table.  Simple taps guide you through the elements and a swipe reveals specific information for the selected element:

The data included for each element is as follows:

Name of Element
Atom Number
Symbol
Atomic Weight
Phase
Type
Group
Period
Electron Configuration 
Ground State Level 
Ionization Energy 
Melting Point
Boiling Point
Crystal Structure
Atomic Radius
Metallic Radius
Covalent Radius
Atomic Radius Calculated
Van Der Waals Radius
Electron Gravity
Density
Electron Affinity
Thermal Conductivity
Electrical Resistivity
CAS Number
Possible Oxidation States
Discoverer
Discovery Year

Release notes:
This version has been updated to recommended settings and provides better compatibility with later versions of iOS. This version supports iPad Pro (3rd Gen) 12.9" displays.