Facebook Messenger commonly known as Messenger, is an instant messaging tool parented by Facebook. Messenger is just like texting with your mobile phone, except one does not have to pay for messages. However, a WiFi connection is needed to send the messages to others. Calls are free, but one would be charged for data if they are not connected via WiFi. Many can instantly connect with people in their life, but the person would have or make an account with Facebook to use the Messenger App.
Formerly a part of Facebook mobile application, a recent update makes it so that messages must be sent and received in a separate application on mobile devices.Though Messenger continues to grow, the application has started incorporating different tools such as the microphone and location sharing that are causing privacy concerns from users.
Facebook “chat” was released as part of Facebook in 2011. As a part of Facebook, the service could be accessed by entering the social media platform via mobile device or computer. In April 2014, Facebook changed the name from “chat” to Messenger and created a separate application for mobile devices. To access the Facebook Messaging platforms from a mobile device, the Messenger app must be downloaded. In addition, it now works on all phones, devices and software, including IOS, Android, Windows, and Windows 7, but Firefox was discontinued in 2014. 
By 2015, about 600 million Facebook users utilized this new Messenger platform. In 2016, the algorithm for Messenger changed to a chat box at the bottom of the user’s screen. In 2017, Facebook relaunched the design of Messenger for Android and iOS users. This included a new home screen to allow organization through tabs of categories and content and red dots indicating unopened activity. Messenger continues to expand and recently announced Messenger Kids, designed for users under the age of 13. 
Messenger incorporated the microphone for different uses. Starting in 2013, voice calling was introduced. In 2015, it provided international calling services utilizing WiFi. Later that year, group video calling for up to 50 people simultaneously was enabled.
Photos and videos utilizing the microphone can be taken on the Messenger app to automatically send to other users for free. After users discovered that voice messaging could be used for free, the microphone began being used more often for voices messages. Messenger gives users the option to record their voice and send as the 
Prior to 2015, Messenger had “Live Location.” This feature allowed the app to share your location automatically with other users or group of friends for 60 minutes. You'll be able to be found and Facebook will show how much time it would take to reach the friends whose location is being shared. In 2015, this automatic sharing of location was replaced with static location maps. Any user may choose to click the location button to show themselves on a map. Users can share their locations with friends or groups of friends for certain amounts of time. In March 2017, “Live Location” was brought back; while it is still possible to only share your static location, the default is currently set to use “Live Location.”
On March 17th, 2015, Facebook introduced the ability for users to send payments to friends via Facebook messenger. Their goal was to get users to defer to Facebook payment when chatting with friends when "settling debts or splitting a bill."  If someone desire this new e-payment function through Facebook, a user must connect their Visa or Mastercard debit card to the app and then allows users to tap the "$" button to send money. This service is free of charge and has the goal of competing with other apps like Venmo and PayPal. Facebook built their own payment system from the ground up and claims that all transactions are encrypted, and that all the data on this platform is kept separate from the rest of Facebook.
In 2014, 200 million users were on Facebook Messenger. By 2015, when the app was separated from Facebook, Messenger had 600 million users. In July of 2016, Messenger hit the 1 billion mark, and it was last reported to have 1.2 billion users as of April 2017. 
Build in Functionalities
With a built-in camera, Messenger lets people snap and shoot moments as they happen. They can even add drawings or text to personalize their photos or send them to a friend, a group of friends or post to their Messenger Story.
When a user downloads Facebook Messenger, there are many default settings that are in place. When the app is first opened, the user is notified about settings such as camera, contacts, location and microphone access. The app asks permission to use each of these other features on the device. Additionally, one of the permissions Messenger asks for is for the app to be able to edit, receive, read and send SMS messages. Many people quickly click through each request clicking yes.
Facebook, the parent company to Messenger, made an official comment addressing the public’s concern regarding the microphone listening in on conversations. Despite the large quantity of people who claim to see a change in ads on their newsfeed right after they speak out loud about a product, Facebook publicly stated they do not use your microphone without given permission. However, if a user is taking a video or using the audio call, Messenger is allowed to collect the data that comes through the microphone. This is an exact example of “'The Right to Privacy’, published in the Harvard Law Review in 1890, [where] ethicist Samuel D. Warren and Louis Brandeis warned that privacy was being undermined by recent inventions and business enterprise….” Facebook, the business enterprise, is undermining people through Messenger and exploiting access to videos and audio calls by listening to their audio and utilizing the information for advertisements.
People using Messenger are able to manage their own accounts in order to turn off the microphone access. These are the necessary steps to turn off microphone access:
- Settings app on device
- Turn the switch next to microphone off
Messenger’s location sharing platform has changed multiple times over the past few years. “Live Sharing,” allowed users’ locations to be shared without their knowledge. This violates David Shoemaker’s control theory for information privacy that says that one only has full informational privacy when they have full control over the zone of which personal information is being shared. Therefore, not being able to control with whom and when you are sharing your location is a violation of control theory. It is important to note that users are able to turn off the feature, but Facebook does not readily alert users to which data is being shared and where to adjust their settings.
In 2015, Static Sharing replaced “Live Sharing” of location on the Messenger app. Instead of constantly sharing one’s location, the user has the option to drop a pin anywhere on a map and send it to their friend via Messenger. This allowed people to monitor their privacy and prevented those who were being messaged from tracking their every location. However, in the beginning of 2017, “Live Sharing” was brought back. Experts agree that on smartphones it is now practically impossible to stop location tracking. This once again violates Shoemaker’s policy of control theory through this inability to protect one’s own privacy.
You may gain some control of your privacy by turning off location sharing. These are the steps to turn off location sharing:
- Settings app on device
- Click the messenger app
- Tap location
- Tap never
Facebook Messenger users might send their friends spam or links with viruses unintentionally. Facebook users can have their account hacked and then have messages sent through Messenger on their behalf to anyone on their friends list. Messages could be composed of simple messages urging receivers of the message to "Click Here!" on a video or "like" a page in order to win a Free iPad or gift card. . Hackers target these social media accounts because they know they can easily mine a lot of data. . Some hackers are cybercriminals who want to manipulate the user into buying adware from them. . Facebook Messenger makes if more difficult to track these cybercriminals who want to trick users into downloading adware disguised as a software update in order for the users to be tracked by cookies so they can have targeted ads.  Facebook offer support for users who believe they've been hacked and have messages being sent from their Messenger that they didn't intend to send. Facebook will now provide a free antivirus scan to users if they flag malware on your account.  Some users have complained about these scans because they're unable to log back into their accounts.  Additionally, these antivirus softwares are powerful enough to access nearly all the information on one's computer, making some users uncomfortable with using this service.