It is what is says, a time related algorithm, not encryption; the message is in plain text, the only way with a (remote) portable / mobile APRS radio. The time related algorithm is like a PIN code that changes by user defined steps according to the system time, although not infallible, it would make a radio incursion very difficult.
The program was designed for flexible home automation but it could also prove useful in other areas as stated. The statement "When away, you can control your home / business remotely and securely…" is a general one, you could indeed control a business remotely but via an internet connection or if it’s a business at an isolated location, a commercial radio, licence and TNC could be used, it is not implying that the only means of communication is by amateur APRS radio.
Thank you for your interest.