--- title: The Phone in Your Hand | daily.dev description: A layer-by-layer explainer of the key hardware components inside a modern smartphone. Covers the CPU (general-purpose instruction execution, big/little core... canonical: https://daily.dev/posts/the-phone-in-your-hand-ob7f2udy9 twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: The Phone in Your Hand | daily.dev og:description: A layer-by-layer explainer of the key hardware components inside a modern smartphone. Covers the CPU (general-purpose instruction execution, big/little core... og:url: https://daily.dev/posts/the-phone-in-your-hand-ob7f2udy9 og:image: https://api.daily.dev/og/posts/ob7F2udY9.png og:image:alt: The Phone in Your Hand og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # The Phone in Your Hand **[Hacker News](https://daily.dev/sources/hn)** · 2 min read · 0 upvotes · 0 comments ## Summary A layer-by-layer explainer of the key hardware components inside a modern smartphone. Covers the CPU (general-purpose instruction execution, big/little core design), GPU (parallel pixel rendering), NPU (pattern recognition and AI workloads, introduced in flagship phones around 2017), memory hierarchy (cache, RAM, flash storage), and the Secure Processing Unit (isolated vault for biometric and payment data). ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### What is the difference between a phone's CPU and GPU? A CPU executes instructions step by step, fetching, applying, and committing operations like additions, and can complete tens of billions of instructions per second across six to eight cores split between high-performance and power-efficient designs. A GPU instead uses thousands of parallel processing units specialized for the repetitive math needed to render pixels and turn code into moving visuals on screen. _Comparing CPU and GPU roles helps when reasoning about performance, a topic developers track on daily.dev._ ### What does a phone's NPU do and when did it appear in flagship phones? A neural processing unit performs multiply-and-accumulate operations needed for artificial neural networks and appeared in flagship phones around 2017. Unlike a CPU's precise binary math, an NPU is suited to the fuzzy pattern-recognition tasks like speech, face, and object recognition, and it also powers on-device generative AI features. _Developers building on-device AI features can follow NPU capabilities and trends on daily.dev._ ### What is the difference between RAM and flash storage on a phone? RAM is fast working memory that must stay powered to retain data and holds actively running software, while flash storage retains data without power, is slower than RAM, but is still dozens of times faster than older spinning hard drives, and stores installed software and user files long-term. _Understanding memory tiers matters for developers optimizing app performance, a subject worth following on daily.dev._ ## Similar posts on daily.dev - [CPU vs GPU vs TPU vs QPU: The Complete 2026 Guide to Modern Processors](https://daily.dev/posts/cpu-vs-gpu-vs-tpu-vs-qpu-the-complete-2026-guide-to-modern-processors-utp5fgiot) · Medium · 0 upvotes · 0 comments - [The Hardware That Makes AI Possible](https://daily.dev/posts/the-hardware-that-makes-ai-possible-oso4ilnea) · Towards Data Science · 0 upvotes · 0 comments - [3 reasons Google's Pixel still feels unlike any other Android phone](https://daily.dev/posts/3-reasons-google-s-pixel-still-feels-unlike-any-other-android-phone-xfudlisf5) · XDA Developers · 2 upvotes · 0 comments --- Tags: [#architecture](https://daily.dev/tags/architecture), [#gpu](https://daily.dev/tags/gpu), [#computing](https://daily.dev/tags/computing) [View this post on daily.dev](https://daily.dev/posts/the-phone-in-your-hand-ob7f2udy9) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"The Phone in Your Hand","url":"https://daily.dev/posts/the-phone-in-your-hand-ob7f2udy9","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/the-phone-in-your-hand-ob7f2udy9"},"datePublished":"2026-08-11T21:36:05.174Z","dateModified":"2026-09-14T06:17:42.073Z","description":"A layer-by-layer explainer of the key hardware components inside a modern smartphone. 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