Exercises: Mobile phones, tablets and other devices

Name three components that your cell phone shares with a computer and explain in one sentence what each one does inside the phone.

Think about these devices: laptop computer, tablet, cell phone, game console and e-reader. Choose three of them and explain one task for which each is better than the others.

The figure compares a computer and a cell phone: the central capsule shows the components they share, but one is missing, as shown in the diagram.

Which shared component is missing from the capsule and what is it used for? Look also at the differences shown below each device and explain a task in which the computer wins and another in which the cell phone wins.

Name the device corresponding to each description: (a) fits in a pocket and is used to make calls; (b) has a large screen designed for reading for hours without eye strain; (c) connects to the TV and is operated with a controller for gaming; (d) is worn on the wrist and tracks your steps.

Name three things that a cell phone and a tablet have in common (touch screen, battery, apps...) and one important difference between them, explaining how that difference is noticed when using them.

Explain what a device battery is and why desktop computers do not need a battery to operate, whereas cell phones, tablets and laptops do.

A handheld console has a screen, battery, CPU and memory, like a cell phone. Do you think it is more similar to a cell phone or a desktop computer? Defend your answer with two arguments.

An e-reader lasts for weeks without charging and a tablet only lasts a few hours. Relate this difference to their screens (E Ink vs. bright touch screen) and to the amount of calculations each device performs.

You have to do three tasks: write a long essay, edit a photo for a presentation, and inform your group of a change of plans. State which device you would use in each case (cell phone, tablet, or computer) and justify your choice considering the screen, keyboard, and comfort.

A tablet with a keyboard case costs almost as much as a laptop computer. Analyze two advantages and two disadvantages of studying using only the tablet (notes, assignments, online exam) and conclude whether you think it could replace the laptop in your case.

A cell phone has $64\ \text{GB}$ of storage and each photo takes up on average $12\ \text{MB}$. Knowing that $1\ \text{GB}$ is equivalent to $1\,000\ \text{MB}$, calculate using the division $\frac{64\,000\ \text{MB}}{12\ \text{MB}}$ how many photos would fit if the cell phone were empty, and then explain two reasons why in reality significantly fewer fit.

Your grandfather wants a device solely for viewing family photos, making video calls and reading the online newspaper. Choose between a cell phone, tablet or computer, and justify your choice considering screen size, simplicity of use and where he will use it.

Compare writing a four-page essay on a cell phone using an on-screen keyboard with writing it on a laptop: analyze the speed, comfort and errors you would make in each case, and describe a situation in which the cell phone would indeed be a good option for writing.

An e-reader has $8\ \text{GB}$ of storage and each book takes up on average $2\ \text{MB}$. Calculate using the division $\frac{8\,000\ \text{MB}}{2\ \text{MB}}$ how many books fit and estimate how many years you could read at a rate of one book a day (a year has $365$ days). Comment on whether it makes sense to worry about space on this device.

A new cell phone is smaller and lighter than one from five years ago, yet it has a better camera, more memory and a larger battery. Explain how it is possible for devices to improve while becoming smaller (miniaturization of components, greater efficiency) without resorting to "magic".

A "water-resistant" cell phone and a normal one fall into a puddle. Explain what it means for a device to be sealed against water and dust, and name two other everyday devices gaining this protection (watches, earphones...), explaining why they need it.

You are on a mountain hike, you only have 15% battery left, there is almost no coverage on any stretch, and you need the phone to stay on for 4 hours to let people know when you arrive. A friend tells you: "Set the screen to maximum brightness to see well in the sun, leave GPS and cellular data searching for a signal in case a message comes through, and close and reopen the maps app every five minutes so it doesn't consume battery". Critically analyze why these three pieces of advice drain the battery much faster, linking it to the processor, the screen, and the modem. Then, design the optimal technical protocol of 3 settings that you should activate immediately so that the device survives until the end.

A photographer travels for two weeks doing reports: she needs to review and select photos every night, write articles and send them, and does not always have access to power outlets. Choose between a laptop, tablet or cell phone as the main device for the trip, justify your choice (screen, battery life, weight, storage) and explain which accessories you would recommend to her.

Your older brother is offered the chance to upgrade his 3-year-old phone to a new 300 dollars model. His current phone runs smoothly, but the battery only lasts 4 hours and the "Storage almost full" warning keeps popping up constantly. The store employee tells him: "That phone is already junk; it's more cost-effective to buy a new one than to try to fix it". Technically refute the store employee's argument: 1) Propose two low-cost technical solutions (one hardware and one data management) to restore its battery life and free up space without replacing the device; 2) Justify the environmental impact avoided by your proposal compared to buying a new phone, mentioning the savings of raw materials and the reduction of electronic waste.

A friend states: "Handheld consoles no longer make sense because any mid-range cell phone has a faster processor and a better screen". Refute their statement by analyzing two technical problems a cell phone suffers from when running demanding games for two consecutive hours (thermal throttling and accelerated battery drain) compared to the active cooling system of a console. Then, design what three hardware features (physical or thermal) a cell phone accessory should incorporate if it aims to compete on equal terms with a dedicated handheld console.