Answers

@ArnoldUlate - Yes, you can test on your own iPhone. You will need a Mac though, even if you use Visual Studio for your IDE. (You might be able to use http://www.macincloud.com/ if you haven't got a Mac, but I've never tried it - perhaps somebody else can confirm that).
Thanks @JohnHardman
My question is: To compile the iOS application, do I need to have a mac in my domain?
Accepted Answer
@ArnoldUlate - The standard answer is - yes, you need a Mac to build your iOS application, even if you use Visual Studio on a PC as your main development environment. The documentation at https://developer.xamarin.com/guides/xamarin-forms/getting-started/installation/ says 'A networked Mac is required for iOS development.'
The less frequently heard answer is that you may be able to use http://www.macincloud.com (I've never done that, so cannot confirm that it works for Xamarin.Forms development and cannot confirm that it meets licensing terms).
If you get a physical Mac, you either want it nearby, or you will want to VNC to it occasionally, when certain things you want to do have to be done directly on the Mac.

No, Visual Studio 2015 for Mac is not exists. Before VS2017 for mac, there is a preview version, details please refer: Announcing the new Visual Studio for Mac If you could not work with VS2017 for MAC and want to connect to TFS/VSTS. Feb 04, 2019 Visual Studio 2019 for Mac version 8.4 Preview 1 (8.4.0.1935) released October 17, 2019. We made a number of changes to address accessibility in this release including: Increasing contrast in a number of areas with low contrast. Issues with VoiceOver in the debugging experience.

-->

Visual Studio for Mac distributes updates for the IDE and supported frameworks on a regular basis. These updates can be in the form of new features, improvements, and bug fixes.

Visual Studio for Mac provides two channels to get these latest versions:

Stable - Provides thoroughly tested updates. This channel is recommended for the best development experience.
Preview - Provides early access to updates that are candidates for release in the Stable Channel. These releases may not be reliable for everyday use.

Checking for updates

You can use the Visual Studio Updater box to check for new updates, change channels, and download and install updates.

To open the Visual Studio Updater, browse to Visual Studio > Check for Updates:

This displays the updater box:

Changing the Updater channel

To change the channel select it from the channel drop down and press the Switch Channel button:

Downloading and installing updates

Switching channels automatically starts the download process of new updates.

If you have selected the option to Check Automatically, the updater box will pop up when Visual Studio for Mac is open to let you know that new updates are available. New downloads will start downloading automatically to your machine when this box appears.

To start installing updates, select the Restart and Install Updates button:

Depending on the components that need to be installed, you may need to accept additional licenses or enter your machine's administrator username and password.

Troubleshooting

Visual Studio For Mac Preview

If you have issues with the updater, try following the steps in the Updater Troubleshooting guide.

Visual Studios For Mac