Fix dollar signs + add descendants section

# [TECH] Mobile Phones & Smartphones

**Mobile Phones** untethered telecommunications from fixed infrastructure; **Smartphones** (iPhone, 2007) merged phone, computer, camera, GPS, and internet into a pocket device now used by 5 billion people.

## Overview

The first commercial cellular networks (1G, Motorola DynaTAC, 1983) were voice-only. 2G (GSM, 1991) added SMS; 3G (2001) added data; 4G LTE (2009) enabled video streaming. The iPhone (2007) and Android (2008) created the smartphone era. Mobile internet users now exceed desktop; mobile commerce exceeds \$4T/year. 5G (2019–) enables IoT, autonomous vehicles, and ultra-low-latency applications.

## Key Actors

- **Companies**: Motorola (DynaTAC, 1983), Nokia (dominant 1990s), Apple (iPhone 2007), Samsung, Google (Android), Qualcomm (chipsets), TSMC (Apple Silicon)
- **Inventors**: Martin Cooper (1928–, first mobile call 1973), Steve Jobs (1955–2011)

## Key Patents

- Cooper, M. US Patent 3,906,166 (1975) — portable radio telephone (Motorola)
- Apple's multitouch iPhone patents (2007, hundreds of patents)

## Economic Value

Global smartphone market: **\$520 billion/year** hardware (IDC 2023). App stores and mobile services: \$700B+/year. Mobile commerce: \$4.5T/year (eMarketer 2023). Total mobile economy (GSMA): **\$5.2 trillion/year**.

## Notes

IDC *Smartphone Market Share* 2023. GSMA *Mobile Economy* 2023. App Store (Apple, 2023): \$1.1T in developer billings/sales.

## What This Enables
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- **[TECH] Internet & World Wide Web** — Mobile internet now accounts for >60% of global web traffic; smartphones drove the mobile-first internet.
- **[TECH] Cloud Computing & Big Data** — Smartphones are the primary clients of cloud services: photos, maps, AI assistants, and streaming all run in the cloud.
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# Parents

* [TECH] Integrated Circuit
* [TECH] Radio & Wireless Communication
* [TECH] Integrated Circuit
* [TECH] Satellite Communications
* [TECH] Semiconductor Lasers & LEDs
* [TECH] GPS (Global Positioning System)