Incense

IncensePoke stop - thepokemonguide.com

You’ll need to start attracting more Pokémon from the start so you can catch them and get a larger team. When you start the game, you’re given 2 Incense pots, which are meant to get you going. Activating them will emit a fragrance that’ll have the Pokemon drawn to your presence like bees to honey. These incense pots can be found in the items menu (tap the PokéBall at the bottom of the screen).
Incense draw in nearby Pokémon by giving off a mysterious fragrance.
Each incense pot lasts 30 minutes. Timing is everything — once you activate the incense, a timer starts counting down and keeps counting down even if you leave the app.