iPhone
The iPhone 15 Pro measures 146.6 x 70.6 x 8.25 millimetres and weighs 187 grams. Apple's engineering teams have devoted considerable resources to minimising these dimensions whilst maximising internal componentry. The device's form factor represents decades of miniaturisation research.
In volumetric terms, one could theoretically fit approximately 2.56 x 10^26 iPhones inside the Moon's volume. Apple's current manufacturing capacity would require roughly 1.28 x 10^18 years to produce this quantity.