One of the biggest problems with this sort of information is visibility. People go out of currency because they have not noticed. The information is in every pilots licence/logbook but they don't look. Whilst there are many software solutions, it still depends upon the visibility of that information, and in most cases, that will require a system which automatically flags up dates as they get close. Incidentally, there are no such things as "bianuals" which mean twice a year! There is not even a requirement for a biennial, it is but one option in a multi choice process.