From the online sales pitch, it seems hard to tell exactly what this product does. It appears to be a database where each document gets a number, the user assigns tags, then when you go to look for something, it's in numerical order, not alphabetic.
Assuming I've got that right, it would be a breeze to set something like this up in Bento or Numbers or Tables or Excel.
As far as the electronic document portion, there's lots of software to fit that bill. EagleFiler, RecordsMaster, Yojimbo, Yep, Together ...
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