The life cycle of a smartphone begins in mines around the world. There, raw materials and rare earth metals are extracted from the planet in an energy-intensive process.
Those materials get transported to factories where they're refined, often using high temperatures and significant energy, and turned into components like batteries, wires, logic boards and motors. The components are then transferred by fossil fuel-powered vehicles to yet more factories to be assembled into complete devices, before being shipped to consumers around the world.
As taxing as this manufacturing process is on the environment, it's only made worse by how quickly most consumers discard their phones. Manufacturers have made it difficult to repair devices, and replacing them is often an easier and less expensive solution for consumers, further contributing to the already-dire climate crisis.