From Randall Glass:
RadioTelephone Tutor uses adaptive tutoring to prepare you for the FCC exams.
It targets questions, that you are weak in. The weaker you are on certain questions, the more it will drill you on those questions.
It keeps on drilling, until it decides, that you know the answers to those questions.
Creates practice test, like you would be given in a real exam.
Speeds up preparing for the exams.
Always up to date, and upgrades are free.
Cheaper than most study books.
More expensive than some GROL prep sites, but only if your time isn't worth anything.
Besides the windows version, a dos version is available for the Android, IPad & IPhone using a dos emulator.
The questions and answers are available in MP3 audio format.