The major system (also called the phonetic number system, phonetic mnemonic system, or Herigone's mnemonic system) is a mnemonic technique used to aid in memorizing numbers. More on that on wiki
MajorSystem app is a training tool for creating/memorizing images that represent numbers. It supports creating and editing your own "number - association" dictionaries. It also comes with two preexisting dictionaries, English and Croatian.
It is meant to be used like memorandum, quick reference to remember association for certain number. For quick installation just download "majorSystem.apk" and install it on your Android device.