Phonogram Sounds is a program designed for Mac users who start learning the basics of English phonetics. By working with this speech application you can study the correct pronunciation of phonograms which are individual letters and groups of letters.
The utility consists of lists with the letters from the alphabet, groups of consonants and vowels, and other phonograms. All you need to do is click over one of the listed letters or group of letters and a text-to-speech tool plays the sound of the phonogram accordingly.
Other than that, not much more can be said about this application. It simply does what's being stated on the homepage of the developer.
In my opinion, the program is missing some features. For instance, you cannot choose between speaker types (female or male - other apps offer you this option), adjust speech volume, etc. These options are usually found within a Preferences menu which is absent in Phonogram Sounds.
To summarize, Phonogram Sounds is a Mac application that might prove to be of good use to people who wish to learn how to pronounce phonograms in English. The program is very simple to use and comes without a price tag. So, I can't find any harm in trying this speech utility on your computer.