The Rotom Pokedex was first introduce in Pokemon Sun & Moon, where Rotom would inhabit your Pokedex and help your trainer along the way with certain tips and advice. In Pokemon Sword & Shield, Rotom once again inhabits a device that belongs to your trainer, this time a phone. The Rotom Phone works similarly to the Rotom Pokedex, since the Rotom Phone will still act as your Pokedex and will keep track of all the Pokemon you Encounter during your journey. However, it won't constantly need attention and it won't give as many tips as the Rotom Pokedex once did.
On top of acting as your Pokedex, the Rotom Phone will also have an additional feature of a becoming a Bike. You will earn this access after defeating Team Yell on Route 5, and the Bike helps players get to places much faster than on foot. Later in the game, your bike will even become equipped to traverse over water! With the Rotom Phone, you no longer need a Pokemon to travel across the waters of a region!
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