Mobile Device Accessories and Ports
By Dave Prowse
Date: Sep 24, 2022
This sample chapter from CompTIA A+ Core 1 (220-1101) and Core 2 (220-1102) Exam Cram, covers A+ 220-1101 Objective 1.3: Given a scenario, set up and configure accessories and ports of mobile devices.
Connection Types
Depending on what you need to accomplish with your mobile device, you might require a wired or a wireless connection. Let’s discuss these now.
Wired Connections
Wired connections use physical ports. If you have ever plugged in a mobile device to charge it, then you have used a wired connection.
The most common wired connection is USB. USB has been around for a long time and has gone through several versions and port changes. USB is used by devices that run Android and Windows (among others). However, aside from USB-C, iOS-based devices from Apple use the proprietary Lightning connector. Figure 3.1 shows examples of the ports and connectors that you should know for the exam, including Mini-USB, Micro-USB, USB-C, and Lightning.
FIGURE 3.1 USB and Lightning ports and connectors
Almost all device charging cables use a standard Type A USB port on the other end, regardless of the connector type that is used to attach to the device. This allows connectivity to the majority of charging plugs and PCs and laptops in the world. However, there are tons of adapters out there, so be ready.
As of the writing of this book (2022), USB-C is common for many Android-based smartphones and tablets. Previously, and for many years, Android devices used Micro-USB, but USB-C has been the dominant port on new devices since at least 2019. Even some Apple devices started using it in 2019. On the other hand, Mini-USB is quite uncommon, but you might see it on older devices, such as accessories for smartphones.
Another purpose of a wired port is to make it possible to tether the mobile device to a desktop or laptop computer (usually via the computer’s USB port). This tethering can allow a desktop computer or laptop to share the mobile device’s Internet connection. Tethering functionality can be very useful in areas where a smartphone has cellular access but the PC/laptop cannot connect to the Internet. Once the physical USB connection is made, USB tethering can be turned on in the OS settings (where you will usually find the Mobile Hotspot option as well). Keep in mind that Wi-Fi capability on a smartphone is usually disabled when USB tethering is enabled and that the user must have hotspot service with their cellular provider for USB tethering to work.
Some mobile devices can also be equipped with serial interfaces (RS-232) or adapters from USB to serial. This allows for testing of devices and connectivity to various networking equipment and industrial devices. We will discuss serial interfaces and RS-232 in Chapter 13.
Wireless Connections
Wireless technologies are what really make a smartphone attractive to users. Most people would rather do without cables, and technologies such as Bluetooth, near-field communication (NFC), and hotspots make a smartphone functional and easier to use.
Given the inherent mobility of smartphones and tablets, most technologies regarding communications and control are wireless. If designed and configured properly, wireless connections offer ease of use, efficiency, and even great speed. We’ll discuss Wi-Fi, cellular, GPS, and similar data-related wireless technologies later in the book. For now, let’s focus on wireless connections used by mobile devices to communicate with accessories and other mobile devices.
One of the wireless technologies most commonly used is Bluetooth. Bluetooth enables users to incorporate wearable technology (such as headsets, earpieces, earbuds, and smartwatches) with their existing mobile devices. But the technology goes much further; for example, it allows for the streaming of music to external speakers and an automobile’s music system. Bluetooth is usually limited to about 33 feet (10 meters), which is the maximum transmission distance for Class 2 Bluetooth devices.
Another commonly used wireless technology is the mobile hotspot. When enabled on a properly equipped smartphone or tablet (with 4G or faster connection), a hotspot allows a user to connect desktops, laptops, and other mobile devices (wirelessly, of course) through the device running the hotspot, ultimately allowing access to the Internet. This can be a great way to connect your laptop or other computer if Wi-Fi goes down, often with speeds rivaling wired Internet speeds. But remember, there’s usually a catch! Many providers charge for data usage (unless you have a corporate plan). Because of this, a hotspot is often used as a secondary connection or as a backup plan. In addition, the further the hotspot-enabled mobile device is from a cell tower, the lower the data transfer rate. So know the pros and cons of running a hotspot on a mobile device.
Next, let’s discuss near-field communication (NFC). This allows smartphones to communicate with each other via radio frequency by touching the devices together or, in some cases, by simply having them in close proximity to each other. NFC uses the radio frequency 13.56 MHz and can transmit 100 to 400 kb/s. It doesn’t sound like much—it transfers more slowly than Bluetooth, for example—but it’s usually plenty for sending and receiving contact information, MP3s, and even photos. Besides working in peer-to-peer mode (also known as ad hoc mode), a full NFC device can also act like a smart card performing payment transactions and reading NFC tags. If you are not sure whether your device supports NFC, check the settings in the mobile OS. Most smartphones incorporate NFC technology.
Accessories
Well, a person has to accessorize, right? It almost seems a requirement with today’s mobile devices. Probably the number-one thing that people do to augment their device is to protect it—using protective covers or cases, plastic or glass-based screen protectors, waterproofing, car mounts, and so on.
Then there’s add-on storage. You can never have enough memory, right? Adding long-term storage is usually accomplished with the addition of a microSD card (for example 32, 64, or 128 GB). It is common for people who shoot a lot of videos (or a whole lot of photos) to need more memory than the mobile device comes with when purchased. Some devices allow for add-on storage via a slide-out tray on the side of the device. Others don’t allow upgrades.
Next on the list are audio accessories. The 3.5 mm audio jack (if you have one) allows a user to connect headsets, earbuds, or small speakers. Or you can connect a 3.5 mm-to-3.5 mm cable from your phone to the auxiliary port of your car radio or your all-in-one music device—though Bluetooth is usually the easier option. When it comes to music, you can connect a mobile device to anything, such as TVs and music players, given the right cable or adapter. A person can even use a device when performing a live event. The possibilities are endless. And today’s mobile device audio ports can be programmed in such a way as to accept special credit-card readers and a host of other devices. Appliance repair persons and other workers who need to be paid onsite might make use of this technology, though that can also be accomplished in a wireless fashion.
Most of today’s devices cannot be opened by the consumer without voiding the warranty. So, replacing a battery is not as easy as it once was. To do this, a heat gun and proper shims are required. However, if not done correctly, it can defeat the IP rating (more on IP code in a bit). That’s why manufacturers require that battery replacements be done at authorized repair centers. More important when it comes to accessories are battery chargers. Smartphones and tablets can be charged with their included AC chargers or possibly with wireless chargers, where the unit is laid down directly on the charger. A user might also opt to use a “power brick,” which stores a charge for a long time. Keep in mind that these battery packs take a long time to charge up themselves.
Docking Stations and Port Replicators
A docking station expands a laptop so that it can behave more like a desktop computer. By connecting a laptop to a docking station and adding a full-size keyboard, mouse, and monitor, the user doesn’t actually touch the laptop except perhaps to turn it on. Some laptops can hot dock, meaning they can connect to a docking station while powered on. The docking station recharges the laptop’s battery, and possibly a second battery, and has connections for video, audio, networking, and expansion cards. Docking stations might even have an optical disc drive, an additional hard drive, and additional display and USB ports; it all depends on the brand and model. If all these extras aren’t necessary, a user might require only a port replicator, which is a similar device but has only ports (for example, video, sound, network, and so on). Sometimes these are just referred to as docking stations as well.
Drawing Pads, Touchpads, and Touch Pens
A mobile device’s screen is often small, and it can be difficult to manipulate with your fingers. Sometimes a mobile device is not entirely accessible to your hands, perhaps because it is being used as a desktop replacement. And so, necessity breeds invention—in this case easier manipulation in the form of drawing pads, touchpads, and touch pens.
A drawing pad is a flat tablet that allows you to use a stylus to “draw” on the screen of a mobile device. It can be used in illustration programs, slideshows, teaching utilities, and complex programs that have very tight interfaces where the tip of a stylus will work much better than your finger.
A stylus is often referred to as a touch pen or stylus pen. A touch pen can be used by itself with a mobile device to increase the accuracy of input to the screen.
A touchpad (or trackpad) is used to take the place of a laptop’s touchpad; it is much larger and easier to manipulate. It is usually connected via USB or Bluetooth.
Always check whether a mobile device’s operating system will support any of these devices before purchasing and installing them. Installing such accessories is usually very easy as they are typically either plug and play or configured within the Bluetooth properties.
We could go on for days about the accessories available for mobile devices, and we’ll discuss the concepts more later in the book, but that should be enough for the exam for now. Remember, protecting a mobile device and protecting its memory capacity are crucial. The rest of the things we have discussed enable a user to increase functionality or just plain make it more fun, but these things are usually not essential to the device performing its job. Plus, in a bring your own device (BYOD) or choose your own device (CYOD) environment, the users are often quite limited when it comes to accessorizing to prevent compatibility issues and to avoid security vulnerabilities.
Chapter 3 is in the books, so to speak. Excellent work! Keep going!