In a Different World with a Smartphone by Fuyuhara Patora

Translated from Japanese Action Comedy Fantasy Romance Adventure Transported to Another World Harem Magic Royalty
Oh no, the MC is accidentally killed by a god. Because of the mistake, the MC starts a second life in a parallel world. God revives his body and he is allowed to take and use his smartphone. He comes across various people while making important comrades and before the MC is aware of it, he has discovered this world’s secret. He inherits the legacy of an ancient civilization and he goes around the world nonchalantly while having power that matches that of the god in this world.

Alternative names : Isekai wa Smartphone to Tomoni