I'm no expert, but in my opinion I don't think they're worth too much undeveloped - datingnavigator could have potential to be developed into a site which reviewed/advertised dating sites. Not too sure about what a dating gadget could be so can't think of any development potential.
Anyway, I'd say mid $xx datingnavigator with potential for $xxx's developed and maybe low $xx for datinggadget
As I say I'm no expert at this so I may be way out..