Poké Balls are items that are critical to a Trainer's quest, used for catching and storing Pokémon. Currently Poké Balls can be obtained through several different ways such as: spinning Photo Discs at Gyms and PokéStops, being rewarded for leveling up, completing research tasks, opening gifts or purchasing them in Shop (in this case only regular ones).
There currently five varieties of Poké Balls exist in-game:
Regular Poké Balls are the most common and have the lowest success rate in term of capture. The rate increases with the Great Ball, and above.
To see currently owned Poké Balls player can check them out on the item bag page .
When encountering a Pokémon in the wild, players can attempt to catch a Pokémon by holding down on the Poké Ball, sliding upwards, and letting go to launch it towards the Pokémon.
Players can influence bonuses on catching Pokémon by aiming the ball towards the center of the Pokémon while letting the circle indicator shrink down. The closer the ball is to the center, the better bonus you'll get. Players can also hold down the ball and spin it for a curveball bonus that grants additional experience. Selecting a better type of Poké Ball will make the Pokémon easier to capture.
Details Also referred as Regular ones.
Poké Ball is most-common, the lowest-tier device for capturing wild Pokémon. 50 is given upon starting an account. This kind of Poké Ball is a reward for levelling up at from levels two to eleven.
In-game description A device for capturing wild Pokémon. It's thrown like a ball at a Pokémon, comfortably encapsulating its target.
It is high-performance Poké Ball that increases Trainer's chance of capturing a Pokémon by 50%.
Great Balls are unlocked once the player hits Level 12 (however, it is possible to obtain them from certain Special Research tasks prior). Upon levelling to 12 the player receives 20 free Great Balls and they become available via spinning Photo Discs. This kind of Poké Ball is a reward for levelling up from levels 12 to 19.
In-game description A good, high-performance Poké Ball that provides a higher catch rate than a standard Poké Ball.
It is high-performance Poké Ball that increases Trainer's chance of capturing a Pokémon by 100%.
Ultra Balls are unlocked once the player hits Level 20. Upon leveling to 20 the player receives 20 free Ultra Balls and they become available via spinning Photo Discs. This kind of Poké Ball is a reward for leveling up from levels 20 to 40.
In-game description An ultra-high performance Poké Ball that provides a higher Pokémon catch rate than a Great Ball.
It is a type of Poké Ball that can catch a Pokémon without fail. It has not been officially implemented into gameplay yet, although it can be found in the game's data.
In-game description The best Poké Ball with the ultimate level of performance. With it, you will catch any wild Pokémon without fail.
Based on which Trainers controlled the Gym, how much each Trainer contributed as a team during the Raid Battle, each Trainer will receive a variable number of Premier Balls. It unlocks at level 5. These can be used to capture the Raid Boss, once it has been defeated.