Yes, the app can be configured to meassure by weight, but that's not really what sets it apart imho(alltough it's a dealbreaker for me!)...
e-liquid-recipes online calc does it, Scubabatdan's xml calc does it(v14) and ejuicemeup as well, and maybe others I don't know about... What imho makes it different, is it's pre-defined ingridients list/inventory, and one ejuice-file, so you don't have to enter all the flavors used each time, but just use the dropdown-boxes which lists every single flavor in your arsenal, and e.g. your different strength nicbases etc, and you can pre-define the individual ingredients specific gravitys and pg/vg ratio's, so as the author puts it: "You can spend all your time on the recipe instead of the individual ingredients", or something of the sort

...
I only use unflavored myself, so don't really need it, but I mix to others in the family which does preffer flavored mixes...
I know installing wine isn't a problem, but I just preffer to use native linux apps, and when looking a little more deeply, then there always seems to be a linux alternative, or atleast several apps which together provide the same functionality...
I don't really know about this one though

However, I was more interessted in this "theoretically" and impressed about it, more so than it's something that I actually need, or "can't live without". As a windows user, using this app as calc of choise would imho be a "no-brainer"!