Myu's Dad's Smartphone, Arifureta After Stories

Actually, this smartphone was different from the normal smartphone that Myuu took out previously, it was a communication artifact that Hajime created. So that Myuu could use it, it was a type with a magic power storage loaded inside just like Myuu’s other exclusive artifacts; but if it was asked what was its difference with a normal smartphone, then it was at how it was able to communicate with another world.
If one possessed this smartphone, at the very least it would be impossible for the owner to be unable to contact Hajime and others who possessed the same device no matter where they were on earth, so even if the normal smartphone was taken away then there would be no problem, was what Myuu was thinking but……