What do you mean by “backing”? What about just making services that attract customers?
You mean like Angel investors to pay for you to build it before it’s ready for customers?
The only way Grin is going up in value is if it’s used more often and by more people. The only way that happens is by building products with good UX that can compete with Bitcoin Lightning and even Fiat.
So yeah, the only way to pump Grin’s price is by investing in stuff like that. It also benefits developers if they’re holding Grin, of course.
In addition to the ideas I mentioned above, there’s no reason a Grin wallet can’t be equally as good as Venmo or Cashapp.