A Russian-American boy from a family that isn't very well-off. He has various allergies, including animal fur, which led him to take up rock collecting as a hobby since they're safe to touch. He also suffers from asthma and must always carry an inhaler. Due to his family's financial situation, he was the only student in school without a B*Bot, leaving him isolated in a world where kids communicate entirely through them. However, he is a kind, logical, and thoughtful boy who loves science and is quite bright.

A defective B*Bot that fell off a delivery truck while it was braking to avoid Barney. Because his data only updated to the 'A' section and he cannot connect to the Bubble network, even the basic B*Bot algorithms aren't installed, causing various mishaps. He learns how to be a friend from Barney and shows his friendship by 'smiling,' something not in his original code. He tries to make friends for Barney but often ends up causing chaos. His specialty is the 'Digi-Taka' dance.

Barney's friend. She was once close to Barney, but they drifted apart due to his eccentric family and the fact that he didn't have a B*Bot. She is a popular 'influencer' with a huge social media following through her B*Bot. She is one of the few friends who still talks to Barney and shows genuine concern when he is in danger. Later, a school incident turns her into the 'Poop Girl' meme, spreading her most embarrassing moment across the Bubble network, but she is saved when Barney deletes the meme.

A school bully who picks on Barney. Like Savannah, he was once Barney's best friend, but drifted away for the same reasons. He teases and torments Barney throughout the story. When Ron appears with Barney, Rich tries to ignore and kick Ron, only to be hilariously counter-attacked by the defective robot.

Barney's school friend. Like the other two, he was once a best friend of Barney's but is now distant. He is a gaming addict who holds the #1 rank in his game. When Ron accidentally disables the spending limit system on his B*Bot, he immediately spends as much money as possible on microtransactions to upgrade all his game items at once.