How Does Your Smartphone Communicate?

Learn the different ways your smartphone interacts with the rest of the world.

Eric Escobar
4-minute read
Episode #37

Last weekend, I decided to ditch technology and head out into the wilderness. Now I know what you’re thinking and just because I’m a techy doesn’t mean I don’t ever get any fresh air! Anyways, to get back on topic, one of my friends was messing with his smartphone trying to get internet service in the woods. He was baffled as to how it could be that the GPS on his phone worked, but yet he couldn’t send a text message. This spiraled into a great conversation that I thought would be perfect for a Tech Talker podcast.

You probably know that on many of today’s mobile phones you can not only make calls and send text messages, you can also get directions and connect to a wireless headset. What many people don’t realize is how many different types of communication many of today’s smartphones come equipped with. In today’s episode I’m going to break open your smartphone and show you what’s under the hood.

What’s on Your Smartphone Screen?

First let’s cover the basics of what you see on almost all smartphone screens. You see bars of service followed by an E, 3G, 4G, LTE, or if you’re really unlucky, an “O.” The bars will show your signal strength and the symbol identifies which type of network you are connected to. The “O” that I just referred to is one of the oldest types of data transmission out there and is very, very slow. I’ve only seen this appear on my phone a handful of times. The next best in terms of data rate is E, followed by 3G. Keep in mind that there is a difference between the 3G network and a 3G iPhone. Many people confuse these two, but they are entirely different. A 3G iPhone is just a particular model of the iPhone and it also happens to be the name of the third generation wireless network! Confusing, I know.

Now there are 3 new types of communication technologies on the market: 4G, LTE, and HSPA+. You’ve probably heard of 4G (again not to be confused with the 4G iPhone, which is yet another model of the Apple device) and LTE, but HSPA+ is another contender for the future of wireless communication.

These all have comparable data speeds that range from about 5 to 12 megabits per second. However, just so you know, it’s extremely misleading to call any data speeds of this sort 4G. The true definition of 4G is actually 100 megabits per second. I don’t know of a single real world example of a phone communicating at true 4G speeds over HSPA+, LTE, or 4G. At best these should actually be called 3.5G!

Okay now just when you think you have the hang of this, let me throw some more information at you.


I’m sure all of you who have been listening to the Tech Talker podcast are familiar with WiFi, and this is yet another type of communication that is sure to be built into your smartphone. When you have WiFi turned on and you’re connected to the network, your speeds will far exceed what you would normally get from 3G or so-called 4G networks. But the downside is that this will drain more of your battery. However, it’s pretty likely that when you’re connected to WiFi, you’re either at home, at work, in a coffee shop, or someplace else where you can easily charge your device if it drains.


Did you know that most phones built within the past two years have true GPS built into them? This means that even with no cell service whatsoever, your phone can detect your location, pretty much anywhere on the planet. Many people think that if you can’t send or receive calls and text messages, or even download map information over GPS, this means your phone’s locating abilities are disabled. But that’s not true! GPS acts as a one way signal. So your phone receives the information from satellites, but it does not transmit the information back to space. This allows for very small power consumption compared to the other types of communication— and it also explains why my friends couldn’t send text messages from the wilderness even though their phones had functioning GPS.


Next we have Bluetooth. Bluetooth is meant for short range communication. Many of you know Bluetooth as the  thing that allows you to drive in your car while remaining hands free. I’m sure you’re also aware that if you move the earpiece too far away from your device, you’ll lose your connection. This type of communication is not only used for wireless headsets. You’ll also find it in wireless keyboards, headphones, and even mice.

Now that I’ve covered all the basic types of communication at work in your phone, you’re probably thinking, “Hmm, if my phone is constantly sending and receiving signals from all of these different types of communication, shouldn’t that use up a lot of energy?” And you’d be exactly right! All of these signals require energy and that is what uses most your phone’s battery power.

An easy way to shut off this battery drain is to set your phone to airplane mode. Check out these links for easy tutorials on how to do it for your Android, iOS 5, or Windows 7 devices. When your phone is on airplane mode, you won’t be able to send or receive and type of communication, but you’ll notice extreme battery savings.

So here are the 4 ways  you can put this information to use:

  1. If you’re not actively using WiFi or Bluetooth, turn them off to save power.

  2. If you’re out in the wilderness, a smartphone can sometimes double as a GPS.

  3. When you see an advertisement for 4G, just know that it’s not really 4G, but more like 3.5G.

  4. If you want to save a ton of battery power while playing games or watching movies on your smartphone, just switch your phone to airplane mode.

Well, that’s it for today. Be sure to check out all my posts on the Quick and Dirty Tips website. And if you have further questions about this podcast or want to make a suggestion for a future podcast, post your comments on the Tech Talker Facebook page.

Until next time, I’m the Tech Talker, keeping technology simple!

About the Author

Eric Escobar

Tech Talker demystifies technology and cutting edge devices so that even the most tech illiterate can understand what's going on with their computer or gadget — and what to do when something goes wrong.