Lis chaque section en anglais. Le resume en francais ("En bref") est juste un filet de securite : essaie de comprendre en anglais d'abord.
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Mobile devices are a huge part of daily life today. Wearable devices (smartwatches, fitness monitors, glasses, headsets), laptops, tablets, Android phones/tablets, and Apple iPhones/iPads are all examples. Mobile devices are designed to be quick, light, durable, and portable, and for some users a mobile device is their main computer.
A mobile operating system (OS) can be proprietary (closed) or open source. Android is an open source OS based on the Linux kernel, owned by Google, and used mainly on phones and tablets (but also some laptops/PCs). Open source means vendors can take the core code and customize it. Apple's iOS runs only on Apple phones, and iPadOS runs on Apple tablets - both are closed/proprietary. Microsoft Windows runs on many laptops and tablets; Microsoft's own phone operating systems have all been discontinued. Windows 10/11 IoT Core is a version of Windows used on ARM devices. Chrome OS is an open source project from Google (the Chromium OS project); laptops running it are called Chromebooks, popular in schools, and commonly rely on cloud-based apps. Chrome OS is also used on some ARM mobile devices.
Mobile devices need storage. They have RAM (laptops often have as much laptop RAM as desktop computers, though it is sometimes not upgradable in tablets/smartphones). Most mobile devices also use flash memory: nonvolatile, solid-state memory that keeps data even when the power is off. It stores the OS, apps, and data. Flash memory cards for mobile devices include several formats of Secure Digital (SD) card: SD, SDHC, SDXC, SDUC (and likely newer ones released after this book). On Android/Apple devices, use Settings > Storage to see internal memory and any extra card storage.
A device may have a built-in SD card slot or a pull-out SD tray (insert the card with contacts facing down). A microSD card sometimes needs an adapter to fit a full-size SD slot; the adapter must match the mobile device's slot size. A smart card reader (also called a multi-card reader, media card reader, or flash memory card reader) plugs into a USB port (or is built into a laptop) and lets you quickly transfer photos/videos/data from many types of media at once; once a card is inserted, the OS assigns it a drive letter.
Mobile devices also use accessories that are less common on desktop PCs. A headset provides sound over a wired (USB) or wireless (Bluetooth) connection, and fits over one or both ears. A webcam is integrated or USB-connected and records/streams video (a privacy slide can physically block the lens). Speakers can be built in, wired, or wireless (Bluetooth); use Settings to mute/control them. A stylus (touch pen/active pen) provides input on the screen; vendor-specific/proprietary styluses cost more and add buttons/features; a case or screen cover can interfere with a stylus, so check Settings to make sure it is enabled. A mobile docking station gives a stable base for a mobile computer while traveling (e.g., in a police car) and can also charge one or more devices. A track pad/drawing pad is a USB or wireless device used to draw, annotate, or write, sometimes needing the pen calibrated before use. A track point (tracker/tracking device) is a small device used to help locate an important item like a wallet, shown through a companion app.
| Device | Description |
|---|---|
| Tablet | A touch-screen mobile device with camera(s) and microphone that connects to the internet; Apple's version is the iPad (iPad mini, Air, Pro). |
| Drawing pad | Also called a drawing/graphics tablet; used to draw, annotate, type, or write - popular with teachers, artists, space planners, engineers. |
| GPS | The Global Positioning System: satellites providing location, movement, and time data to a device or to a built-in GPS component. |
| Smartphone | Makes calls, runs apps, plays music, tracks movement (GPS), connects wirelessly, and takes high-resolution photos/video. Main OSes: Android and Apple iOS. |
| Phablet | A cross between a smartphone and a tablet, with a larger screen for notes/documents; may include a stylus. |
| E-reader | Also called an e-book reader; has an LCD screen designed for reading and stores digital books/magazines. |
| Smart camera | Has features like facial recognition, inspection, surveillance, and robot guidance; may include a mobile OS and wired/wireless networking. |
| Accessory | Description |
|---|---|
| Headset | Wired (USB) or wireless (Bluetooth) device providing sound, over one or both ears. |
| Webcam | Integrated or USB device for live/recorded video; a privacy slide can block the lens. |
| Speaker | Built-in, wired, or wireless (Bluetooth); controlled/muted through Settings. |
| Stylus | A touch/active pen for screen input; proprietary pens have extra buttons/features. |
| Mobile docking station | Provides a stable environment for a mobile computer while traveling; can also charge devices. |
| Track pad/drawing pad | USB or wireless device for drawings/annotations/text; the pen may need calibration. |
| Track point | A small tracking device that helps locate an item (like a wallet) through a companion app. |
Android.
Chrome OS, developed by Google (as the open source Chromium OS project).
It is nonvolatile solid-state memory, unlike RAM which is volatile.
Settings > Storage.
A track pad/drawing pad; the pen may need to be calibrated first.
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A mobile OS is used mainly with a finger, a stylus, or spoken word instead of a mouse/keyboard. A home screen is shown, sometimes with a system bar across the bottom. A notification area shows icons for battery life, wireless signal, time, and connected media; on a smartphone it is commonly reached by swiping down from the top. An Apple iPad/iPhone may have a physical home button beside or below the screen instead of an on-screen icon.
Touching the display tells the OS to do something. Swiping moves to the next/previous page, photo, or item. Multitouch technology lets a device accept multiple simultaneous touches (two fingers, or a finger and a knuckle). 3-D touch (on devices that support it) does different things depending on how firmly/long you press: a light tap opens an app, tapping and holding does something else, and pressing down firmly does a third thing.
To wake a sleeping device: press the power button and enter a pattern/PIN/passcode if set. On Android, press and drag the lock icon to the unlock icon. On an iPhone/iPad, press the home button, swipe up from the bottom edge, or tap the screen; then slide 'Slide to Unlock' and enter the passcode if required.
| Term | Action | Function |
|---|---|---|
| Touch or tap | Press an icon or area | Opens an application |
| Double-tap | Press an icon/area twice quickly | Enlarges an area of the screen or an item like a picture |
| Long touch / touch and hold | Press and hold on an icon or area | Moves an icon to a different home screen, or unlocks a tablet |
| Swipe or flick | Press and move left/right or up/down | Moves between home screens, or opens the notification area |
| Scroll | Press and move up or down | Quickly goes through a list of files or pictures |
| Pinch or pinch close | Two fingers spread apart moved closer together | Zooms out from an object or area |
| Spread or pinch open | Two fingers close together moved apart | Zooms in on an object or area (e.g. a map or text) |
The ability of a device to accept multiple simultaneous touches, such as two fingers.
Spread or pinch open (two fingers moved apart).
Swipe up from the bottom edge of the screen or tap the screen.
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A cellular network is a set of devices letting phones communicate; it is divided into cells, each covering a specific geographic area. Phones send data through the air to antennas/satellites that relay it onward (cell towers are sometimes disguised as trees).
Cellular networks are described as 3G/4G/5G. Older 3G networks used CDMA (Code Division Multiple Access) or GSM (Global System for Mobile Communications). Starting with 4G, networks use LTE (Long Term Evolution) - each of these is essentially its own 'language'.
International Mobile Equipment Identity (IMEI) is a unique, serial-number-like ID for a specific phone, stored in a database called the Equipment Identity Register (EIR). If a phone is reported stolen, its IMEI can be marked invalid in the database - check a used phone's IMEI against a block list before buying it. The IMEI is commonly printed on the back of the phone, under the battery, or under the SIM card.
The International Mobile Subscriber Identity (IMSI) is a unique number stored on a SIM (subscriber identification module) card. SIM cards are used in phones, satellite phones, other mobile devices, and some laptops, and store personal contacts, phone service info for a GSM network, security authentication data, and a PIN. An eSIM (embedded SIM) is a non-physical SIM built into many smartphones/smartwatches today; it lets you change network provider without swapping a physical card and can support multiple phone numbers - a phone can have a physical SIM plus an eSIM, or two active eSIMs.
| Technology | Description |
|---|---|
| 3G | Third generation; internet connectivity from about 200 kb/s up to 2 Mb/s. |
| 4G | Fourth generation; supports IP telephony, gaming, mobile TV, video conferencing, up to 1 Gb/s. |
| LTE | A version of 4G optimized for video streaming and online gaming. |
| 5G | Fifth generation; up to 20 Gb/s, using some new lower frequencies from 600 MHz to 40 GHz. |
A specific phone (like a serial number); commonly on the back of the phone, under the battery, or under the SIM card.
Contacts, phone service info, security authentication, and a PIN (identified by the IMSI number).
You can change network providers without swapping a physical card, and can have multiple phone numbers.
3G.
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Apps come pre-installed, free, or purchased through the App Store (Apple iOS), Google Play (Android), or Microsoft Store (Windows). Apps have individual settings a user may need help with (e.g., disabling a camera's shutter sound); check the app's own Settings menu, and use Permissions/Privacy to remove unnecessary access to personal information.