December 1, 2015 (Vol. 35, No. 21)
Strong Points: Clean design, lots of information, easy to use
Weak Points: None
Free (in-app purchases)
A nicely designed and useful app, the Amino Acid Tutor Free app allows users to review amino acid structure and the three- or one-letter codes. The user interface is minimalist, but sleekly designed. On the left side of the screen, users can find a list of the amino acids, including structure, name, and abbreviations. Upon selecting an amino acid, users can view additional information for that molecule on the right side of the screen, including a 3D rotating ball-and-stick model, and a number of chemical properties, such as polarity, isoelectric point, and the corresponding codons. In the quiz section of the app, users can test their knowledge with one of five different quizzes. Four of these quizzes have the user identify the amino acid based on chemical structure, three-letter or single-letter code, and polarity, while the fifth quiz asks users whether a given amino acid is essential or nonessential.