Nebia, whose Kickstarter fundraising campaign is due to end Thursday, aims to alter the daily bathing experience by substituting a stream of water with a misty cloud. Apple Inc. CEO Tim Cook and the Schmidt Family Foundation, co-founded by Google Inc.’s Eric Schmidt, have already poured money into it. Nebia uses 70% less water than a normal shower, claims Nebia CEO and co-founder Philip Winter. “It’s where people are least willing to use less water and to make a change,” said Mr. Winter at Nebia’s headquarters in San Francisco. Nebia isn’t a connected consumer product, such as toothbrushes, light...