@reza
I think this is a very clean elegant idea.
I love it! Especially considering I'm living outside of my home country and don't know if I'll ever go back.
I'd happily pay the $4 to send my fav photos, but I'm weird and if you made it free for me, I still would struggle with finding the right photo and sending it to someone I care about. And I really do want to do that!
My suggestion:
I believe ______ has [ this problem] every __(week/month/year)_______. This causes them to _________.
They would be willing to pay ____ every ____ to make it go away.
You can schedule https://calendly.com/billybicket/30min