Rustboro City (2)

Deliver the Devon Parts to the researcher in Rustboro City. He'll also give you a Great Ball. Then, he'll lead you back to the Devon Corp Building. Here you'll meet the company's president himself. During the conversation, the BuzzNav app will be added to your PokeNav. In return, he'll ask you to deliver a letter to Steven in Dewford. Since Dewford can only be accessed by the sea, the president will ask Mr. Briney (the old man who lives in Route 104) to help take you there.

Go downstairs to reach the second floor of the building. The researcher to the southwest will can bring fossils back to life. Remember his location for now then leave the building. Once you're outside, you'll encounter your friend. After the conversation, make your way back to Route 104.