The ChemBalance app contains hundreds of reactions for writing word equations, writing unbalanced equations and balancing equations. In each case, unlimited completion attempts are allowed. A running score is provided along with the results for each problem attempted that can be archived as an email. The answer to any problem is a button touch away. The app’s accepted answer may be compared to the user’s answer on the same screen by selecting “Give Up”. Selecting “Give Up” forfeits the unlimited completion attempts for the presented problem, but can be a useful method for learning how to write and balance chemical equations. In-app help is provided in the form of an explanation with examples of how to write word equations, write unbalanced equations and balancing chemical equations. Synthesis, decomposition, single displacement, double displacement and combustion reactions are included in the randomly presented problems at appropriate levels. Three levels of reaction difficulty are provided. The first level limits the user to three-chemical reactions such as H₂(g) + O₂(g) → H₂O(l). The second level displays four-chemical reactions. The third level with its five–chemical reactions challenges the most advanced users with reactions that go beyond standard five reaction types. The original version of this app, Balancing Chemical Equations, was written by Pat Thayer and marketed by Thayer ChemSoftware LLC and has been used successfully in chemistry classes for over two decades. Short videos of the ChemBalance app in operation can be viewed at chemistryapp.org.