In Another World With My Smartphone

Isekai wa Smartphone to Tomo ni.

Touya Mochizuki was accidentally killed, and as an apology, God allows him to be reborn in a fantasy world and will grant him any one wish he desires. And so, Touya chooses to keep his smartphone in the next world. In his second chance at life, he befriends many important figures and comes across the worlds secret. He inherits the legacy of an ancient civilization and travels around nonchalantly while possessing powers that rival this worlds kings.