I use iHerp to keep track of feeding, sheds and weights. I also use the breeding section to keep track of pairings and copulations. I also put on there who I bought the snake from and when. If the seller provides me with it, I also enter in the hatch date. If I receive paperwork with a snake, I keep it in a file in my file cabinet.
I find iHerp VERY user-friendly. VERY.
I only wish they had a way to backup/download a copy of my tracking info, even if it was to an excel file so that in case something were to happen to their servers...I'd have a backup.