Bernard is a company that is producing dehydrated water in packets of varying sizes, the most popular being the 1 gal capacity.

http://www.bernardfoods.com/foodserv...datedwater.htm

They are also working on a piezoelectric-based water condenser that apparently extracts moisture from the atmosphere. It is available as an app (sorry no Android version available), consumes very little battery and the water exits the iPhone X via its mini-audio jack. Make sure your emergency kit also includes a quarter for the pay phone you'll need to call your crew.