I was reincarnated, so I want a smartphone.

At the moment Ariana is unilaterally told of her broken engagement by her fiancé in the royal capital's social venue, she regains memories of her previous life. She remembers that she was reincarnated from a world called Japan on Earth, and that this world is the stage for "a certain story." Before the disheartened her, an existence calling itself the "Creator" appears and tells her, "I will give you the power you desire." What she wished for was a smartphone, but this world has neither communication networks nor electricity. Instead, she is given something that looks just like a smartphone, but is actually a phantom divine artifact—the "Sage's Grimoire," a magical tool filled with omniscient and almighty knowledge and magic.