Pocket computer, c. 2020s
A slab of glass and aluminium about 8 mm thick that holds a computer, four or more radios, several cameras and a day's worth of energy. It is opened from the back: heat to soften the glue, a suction cup, a thin plastic pick, then a long series of tiny screws.
Closes the back of the phone. It is glass, not metal, so the field from a wireless charger can pass through it.
Made of Aluminosilicate glass toughened in a hot salt bath; the colour is printed or laminated on the inside.
In the salt bath, small sodium ions in the glass swap places with bigger potassium ions. Crowded in, they squeeze the surface into compression, which makes cracks harder to start.
Est. cost to the maker $5–15
Picks up the changing magnetic field of a charging pad and turns it into current for the battery. The black sheet behind it keeps the field out of the electronics.
Made of Flat-wound copper wire, a ferrite sheet, a polyimide flex cable and adhesive.
Pads that follow the common Qi standard work at roughly 100 to 200 kilohertz, far below the radio frequencies the phone uses to talk.
Est. cost to the maker $2–5
Stores the phone's energy: thin coated sheets of electrode and separator, folded into a sealed pouch. Stretchy adhesive strips underneath hold it down.
Made of Lithium-ion polymer cell: graphite anode, lithium cobalt oxide cathode, a porous polymer separator, aluminium-laminate pouch.
The pull tabs at the bottom release the glue: pulled slowly and nearly flat, the adhesive stretches thin and lets go without the battery being pried, which is how it is meant to come out.
Est. cost to the maker $5–12
The phone's computer: processor, memory, storage, power management and radios on both faces of one dense board, under steel cans that stop the chips disturbing each other.
Made of A laminate of glass-fibre and ten or more layers of copper; silicon chips; tin-silver-copper solder; gold-plated contacts.
The processor and its working memory are often stacked one on top of the other in a single package, a trick called package-on-package that saves board area.
Est. cost to the maker $100–250
Two small cameras, a wide and an ultra-wide. Each is a stack of tiny lenses over an image sensor, with magnets and coils that shift the lens to focus and to cancel hand shake.
Made of Moulded plastic and glass lens elements, a silicon image sensor, neodymium magnets, copper coils, a steel and plastic housing.
A phone lens stack can hold six or seven separate elements, each only a fraction of a millimetre thick, all inside a barrel a few millimetres tall.
Est. cost to the maker $15–40
Makes the buzz you feel. A small weight on springs is pushed back and forth by a coil and magnet at the springs' natural rhythm, which gives a crisp tap instead of a rattle.
Made of Steel case, neodymium magnet, copper coil, a tungsten or steel mass, flat springs.
Because it only shakes well at one frequency, this kind of motor (a linear resonant actuator) can start and stop much faster than the old spinning off-centre weight.
Est. cost to the maker $1–4
Pushes sound out through the grille on the bottom edge. A coil glued to a thin diaphragm moves in the field of a magnet; the sealed box behind it shapes the bass.
Made of Neodymium magnet, copper voice coil, polymer diaphragm, a plastic enclosure with an acoustic mesh.
Tiny speaker boxes are sometimes filled with porous beads that make the air inside behave as if the box were larger.
Est. cost to the maker $1–3
The USB-C socket, the bottom microphones and their flex cable. Power and data come in here and run up to the logic board.
Made of Stainless-steel shell, gold-plated contacts on a plastic tongue, polyimide flex, MEMS microphone.
A USB-C socket has 24 contacts in two mirrored rows, which is why the plug fits either way up.
Est. cost to the maker $1–4
The skeleton of the phone, milled from a single block of metal. Everything is screwed or glued to it, and its outer rim is the visible edge with the buttons.
Made of Aluminium alloy (some models use stainless steel or titanium), with plastic-filled breaks in the rim and a graphite heat spreader.
The thin plastic lines across the metal rim are not decoration: they cut the rim into separate pieces that work as antennas.
Est. cost to the maker $10–25
The screen, seen here from behind: an OLED panel whose every pixel makes its own light, a touch layer above it and a cover glass on top. Often the most expensive single part.
Made of Organic light-emitting layers on a glass or flexible plastic base, thin-film transistors, a touch sensor grid, toughened cover glass.
A black pixel on an OLED screen is simply switched off, which is why dark mode can save battery on these phones.
Est. cost to the maker $40–110
Prices are rough ranges of what the manufacturer pays for each part, pieced together from published teardown and bill-of-materials estimates. They vary a lot between models, years and order sizes, and they leave out assembly, software, research, shipping and profit. The drawing shows a generic device, not any particular model.