This is by far the most impressive all around calculator app on the market. The fact that it is just $1.99 and that it goes above and beyond to present answers in as many ways as possible makes this the only calculator app that will definitely increase conceptual understanding for students. The unfortunate part of this app is that the user needs to be connected to the internet in order to use it.
Wolfram Algebra Course Assistant
Common Core State Standards:
A phenomenal calculator that not only solves systems of equations, graphs a variety of equations, computes various expressions and arithmetic, and much much more, but it expands on each of these problem as it presents answers in multiple forms.
Analysis of Change
Modeling & Word Problems
Patterns & Functions
Variables & Expressions
Calculating the answer to various Algebra, Geometry, Trigonometry, and other mathematical problems