The problem that former Sun Microsystems chief executive Jonathan Schwartz is trying to fix with his new startup is clear enough. More and more people are having to care for older relatives or children with health issues as the US population ages. But, the current online methods for sharing such sensitive information aren't always appropriate. Emailing caregiver information can lead to tastelessly targeted ads. Online project management software may be too bloated or insecure for sharing medical histories between just a few people. Offline documents -- the most common form of communication in this area -- are simply hard to share between all the people who need access.