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1 week ago

Pebble Time Round adds polished gold and silver options via Kickstarter

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Pebble has begun taking orders for polished gold and silver versions of its Pebble Time Round smartwatch via its current Kickstarter campaign. The backers will receive the watches before anyone else in September.

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1 week ago

Google to offer free mobile hotspots through Toronto's libraries

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Google is teaming up with the city of Toronto to loan free portable Wi-Fi hotspots to low-income families through the city's public library system. The new initiative is starting at six library branches throughout Toronto, all located in low-income neighborhoods.

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1 week ago

What does rooting your phone actually mean?

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Rooting your phone? Have questions? We have a few answers that explain how root works and what exactly it is.

We love getting your questions. It's always a good thing when we can help each other, and we learn stuff ourselves when looking for the answers. While we can't find time to answer all of them, sometimes a certain question comes up enough that it deserves a detailed answer.

"What does root mean?" is one of those questions. The concept may be simple for some of us, but for many folks who haven't spent time fiddling around with Android or any other permissions-based operating system, it's something to ask questions about. I'm going to try and answer them all as best I can.

Permissions

Before we define root, it's important to understand why it exists and how it works. It's because Android uses permissions (Linux-based permissions, to be exact) in the file structure. Every file, every folder and every partition has a set of permissions. These permissions decide who can read a file (look at or access the contents without changing them), write to a file (be able to change the contents of that file, or create a new file inside a folder or partition) and execute a file (run the file if it's a type that can run, like an app). This is done based on users and permissions — certain users have access, while users who don't have the right permissions are blocked from having access.

When you first set up your phone and turn it on for the first time, you are assigned a user ID. If another user logs in via Google, they are assigned a different user ID. When an app is installed on your phone, it's also assigned a user ID of its own. The system itself is a user and other processes that need to run on your phone may have their own user ID. Everything that can do anything to any files on your Android is a user.

A system of users and permissions is how Android keeps track of who can do what.

Let's say you install a messaging app. It gets assigned a user ID when you install it. It also gets a spot on your data partition of it's own, that only it has access to. You have permissions to execute the app, and when the app runs it has permission to access its own data folder and files. The app may also request permission to access things like your address book or SD card or photo library. If you say yes to these requests (or if you agree to the permissions on older versions of Android) the app's user ID is granted permission to the data files of those things, meaning it can look at the data folder and its contents and possibly change them or add new files. The app can't access any data files it doesn't have permission to "look" at. That means (in our example) it can't do things like look at the settings database, or access the data folder of another application. The term sandbox is often used for this — apps are sandboxed and can only play in the sandboxes they have permission to be in.

For files that are programs and can run (like apps), the same permission model applies. Your user ID has permission to run the apps you installed while you are signed in. The system user has permission to run them and other system-level users may have access to the apps or certain processes the apps use. Other apps can't start up apps they don't have permission to start. If you added a secondary user, they don't have access to your apps or files and vice-versa. There are files, folders and apps on your phone that your user ID doesn't have permission to see, alter or run. Usually those parts of Android require system-level permissions (the system user ID) to do anything with, and you aren't the system user or a user that has system-level permissions.

Switching permissions

While it's technically possibly to change the way your phone boots up and the files it uses to start the running system and assign your user ID elevated permissions, that's neither safe nor practical. But Android (and most Unix or Linux based systems) have what's called a root user, and support the SubstituteUser binary (think of a binary as a small app) to change user IDs. Those are used to administrate the system at the core level.

Because the people who made your phone don't want you to have easy access to the root user ID — and not all the reasons are selfish because it also protects you and your private data — the SubstituteUser binary isn't included in most builds of Android. Without SubstituteUser, we can't switch our user ID. Most system level things in Android have similar easy names, by the way. The core security (files in the bootloader and/or the kernel itself) are also built in a way to prevent you from switching user IDs as part of the SELinux (Security-Enhanced Linux — told you the names are easy) kernel module. Some phones (Samsung's Knox comes to mind) have further protections, and nearly all the companies who make Androids require that, in order to make changes, the bootloader would need to be unlocked so these files can be changed and allow you to switch user IDs. Some phones, like the BlackBerry Priv even go a step further and aren't going to boot if we change anything (even if we could).

To become root, you need a way to change your user ID.

Once we get past all that — either by unlocking the bootloader through authorized means or using some sort of exploit — we can place the SU binary (SubstituteUser) in a spot that it can run when it's called to run — that's called a PATH. If any app is in your user ID's PATH it will run without telling the system exactly where it is. You also need to make sure the SU binary is in a spot that your user ID has permission to execute (run) files. Any other app (Google Play has plenty of apps that need root permissions) will also need the same access. When you use a method to root your phone, all this is sorted out by the folks who built the root method.

Once all that is in place, we can run the SU binary (or another app can run the SU binary).

Getting root access

This is where root comes in. The SU binary uses flags when it's run to tell the system what user ID you want to switch to. For example, if I run the SU binary on my Ubuntu computer like this "su Jim -c nano" I will run the nano command as the user Jim (after supplying Jim's password). If you run the SU binary with no flags or arguments, it switches you to the root user. Normally you would need to supply a password, but since "root" is an unused user on Android it has no password. Running the command "su" will switch you to the user root, and assign you the user ID of 0, and put you in the root group. You are now the Super User.

As the Super User you can do anything to any file, folder or partition on your Android. By anything, we mean literally anything. You can remove bloatware apps and you can also remove essential system files that break your phone. You can also do things to the hardware like change the CPU frequency and ruin your phone forever.

Root is the super user, who can do anything. And we mean anything.

Apps can do the same thing. SU is placed where it's in the application PATH and any app can call it and run it. That app then has Super User permissions, and can do anything it likes to any file any place on your phone. This is why the people who made your phone really don't want you to have this level of access, and the companies who allow you to unlock the bootloader and change things still don't place the SU binary on your phone by default. Having root access with no way to control who or what can use it is dangerous to your phone's software and your personal data.

That's why you need to install an app that forces you to allow root access any time you or another app tries to invoke the Super User permissions. Most times when you use a root method for your phone one will be included, along with some other useful binaries like the BusyBox toolset. If you did things by hand, you'll need to install one yourself. SuperSU by Chainfire in Google Play is a good one to start with.

Odds and ends

Many phones and some root methods do things a little differently (Android 4.3 brought a lot of changes) and require scripts or a daemon (you'll see words like daemonsu or su.d mentioned) instead of just dropping the SU binary in place. These are used to call SubstituteUser so you can switch to the root user just like the raw binary method. The people who figured out how to root your phone have sorted all this out and it will work the same on the user-facing side.

It's also possible to "temp-root" some Androids. This means you can have Super User permissions and do a few things you need to do, but a reboot takes root access away. Likewise, you can have a "shell-root" where you can only access the root user through adb from your computer.

Finally, I want to stress that if you had these questions, you need to consider if you're ready to have a rooted Android. We weren't kidding when we said it's easy to ruin your phone with SuperUser access. There's no reason to be ashamed that you need to do a little reading or ask a few more questions before you do things that can break your phone or give some random rouge app access to all your data.

That's what we're here for.

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1 week ago

AT&T brings Wi-Fi calling to the LG G4

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AT&T has announced that the LG G4 on its network can now make and receive calls, send and receive texts and more all over Wi-Fi instead of requiring a cellular connection. Getting set up is simple: you'll receive a notification that the feature is available and then be prompted to download a small software update. Once that is installed, you can get started.

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1 week ago

Nextbit Robin owners can try out upcoming software with its beta testing program

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Nextbit has announced a new optional beta testing program for owners of the Nextbit Robin. It will allow them to try out upcoming software features and updates before they are released to all owners of the smartphone.

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1 week ago

This microSD card has transfer speeds of up to 80MB/s and is only $10 right now

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Right now you can score Samsung's 32GB microSD card for just $10 at Amazon, a savings of $18 from its normal price. While 32GB may not be the largest card on the market, it is often times plenty of storage to add to your phone or camera. With transfer speeds up to 80MB/s, the card will easily be able to store your pictures, HD video and more with ease.

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1 week ago

OnePlus isn't going to launch a sequel to the OnePlus X

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OnePlus won't be making a sequel to the OnePlus X. At the OnePlus 3 launch event in Shenzhen, CEO Pete Lau revealed to Engadget that the company will focus on one "true flagship" line going forward.

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1 week ago

Samsung Pay is now available in Australia

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Samsung Pay is now available in Australia for American Express and Citibank credit card holders. Customers using either the Galaxy S7, S7 edge, Galaxy Note 5, Galaxy S6 edge+, Galaxy S6 edge, or the Galaxy S6 can now register their cards and start using the contactless payments service.

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1 week ago

It's back: Pick up a 32GB Nexus 5X for just $269

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Last week popular deals site Daily Steals had a great deal on a 32GB Nexus 5X for just $269, and it's made a triumphant return to the site this week. You only have a choice of the black color, but chances are you're alright going with the one color option when you save this much.

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1 week ago

OnePlus 3 is now available exclusively on Amazon India for ₹27,999

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The OnePlus 3 is now official. The Chinese manufacturer's flagship features a metal design, and all the hardware specs you'd expect in a high-end phone in 2016. The phone offers the Snapdragon 820 clocked at 2.2GHz, 6GB of RAM, a 5.5-inch Optic AMOLED screen, and much more for just ₹27,999. The handset is exclusive to Amazon India, and unlike its predecessors, is available without an invite.

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1 week ago

Verizon apparently down in much of Florida

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It's not just you. Verizon Wireless — and in particular the voice end of things — apparently is down in much of Florida. Twitter is aflame. Our inbox is all lit up.

We've shot an email to Verizon to see what's up and will update if and when we hear back. But hopefully they're working on fixing that instead of wasting time on us.

Thanks to everyone who sent this in!

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1 week ago

The Honor 5X starts rolling out to Best Buy stores

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Best Buy has announced that the Honor 5X is now rolling out to its retail stores across the United States. The company hopes to have the 5X out in 590 of its stores by Sunday, June 19. The phone starts at $199.99 unlocked, and comes in gray, silver, and gold.

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1 week ago

Which specs are the most important to you when choosing a phone?

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No matter how much you love your current phone, the time will come when you need to replace it. When day time finally arrives, you'll have more options than you know what to do with. Trying to decide on a phone is a big decision, and that's at least partially because you need to decide what specs, or features, on a phone matter the most to you.

That brings us to this week's poll, we want to know which specs matter the most to you when choosing a phone. There's plenty to consider — maybe you want a higher resolution screen, or access to Hi-Fi audio. With that in mind we've given you 9 options for the poll, covering everything from screen resolution, storage, processing power and camera tech. Hit the poll and let us know!

What is the most important spec when choosing a phone?

Is it hard to decide when it comes to choose a new phone? Is it specs or presentation matter more? Pop in to the comments and let us know how you feel!

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1 week ago

Rhapsody is going back to 1999 and rebranding itself as Napster

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The music streaming service Rhapsody has announced plans to rebrand itself as Napster. The old, and infamous, music sharing service was founded in 1999 and its brand was bought by Rhapsody in 2011.

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1 week ago

How to give your Android phone a Microsoft makeover

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Bringing the look, feel and functionality of Microsoft's ecosystem to your Android phone.

Windows Phone is in an odd place right now — an argument could be made Windows Phone's been in a weird place for a few years now — and whether you have come to Android for more apps, or more consistent experiences, or better hardware, you're here in the Android ecosystem now. But that doesn't mean you have to kiss all your Microsoft and Windows services goodbye.

Whether you're looking to recreate as much of your Windows Phone experience as you can, or you just want to see what Redmond can offer Mountain View, we've got the guide for you. Some devices offer more Microsoft services out of the box, from Cyanogen OS on the OnePlus One to Microsoft productivity suite on the Samsung Galaxy S7 — but there's plenty out there besides.

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