The Anime Lad
After an error involving God, Touya receives a new life in a fantasy world. He is also permitted to keep his smartphone. The local setting has swords and sorcery, while his pocket contains modern apps. Divine compensation has apparently expanded into consumer electronics without clarifying the warranty terms.
Gigguku
The fantasy world has swords and spells. Touya gets to bring his PHONE. That one bonus turns the whole premise into a collision between medieval adventure and modern convenience. He can travel from place to place following whatever catches his interest, with an absurdly familiar rectangle sitting inside all that wonder!
Father's Basement
A smartphone in a fantasy world is a convenience machine disguised as a premise, and the divine bonus makes no claim to hardship. The cleaner appeal is the anachronism. Touya carries ordinary modern technology into a world of swords and sorcery, then follows whichever goal catches his attention. Expect easygoing wish fulfillment, not a survival test.