Very often it is useful to install your app on a device different from the one used for development, where probably Visual Studio is installed so the deploy on it can be simply done running the app in that IDE.

I found the following different way to do that:

• Publish in the Store, setting Distribution and visibility to “Hide this app in the Store. Only customers with the email addresses you enter below can download it, via a direct link”. Then install that app downloading from the Store from the target device as an authorized user.
• Side-loaded via PowerShell onto your test device: see Sebastian Brandes’ post: this was the way that worked also in Windows 8.1. Remind that sideloading is installing and then running or testing an app that has not been certified by the Windows store. (e.g. an app that is internal to your company only).
• Use the WinAppDeployCmd that is a new stand-alone tool available for Windows 10 that is available on your PC in C:\Program Files (x86)\Windows Kits\10\bin\x86 if you installed Visual Studio 2015 or also only Windows 10 SDK (see Install Universal Windows Apps with the WinAppDeployCmd tool). It is like the old 8.1 Application Deployment tool, but this new Windows 10 one is (till now) only a command line tool.
• Use the Remote Tools per Visual Studio 2015 that allows you to do also a remote debugging of your application, further that let you install it on a remote device (e.g. with both PC connected to the same WIFI). See also Set Up the Remote Tools on the Device
  In the following I will give some advices to use the last choice that I think it is very often the  easiest to follow for a developer and also the more useful because allows also a remote debug

First of all if you want to have a package with the appx file created, you have to right click on the Startup project and select Store -> Create App Packages:

Create App Packages

You can also select to build packages not to upload in the Store, in order not to have to sign in with the Microsoft Account and choose one or more platform types you want it runs to: however, in this case, to install and run that app, you have to set Sideload apps or Developer mode in the Settings -> For developer section of your target device.

Side Loading Windows Store app

Platform types choose

Sideload apps or Developer mode in Settings -> For developer section

To do a remote debugging, you have to install in the remote target device the  Remote Tools per Visual Studio 2015 and launch the Remote Debugger app desktop:

Remote Tools for VS2015

Then, on the developer PC, in VS2015 run the app choosing Remote Machine: if both devices are on the same WIFI, an automatic discovery is done, so you only have to select the remote device where you want to launch your app.

Remote Machine Debugging

Auto Detected devices where Remote Tools for VS2015 is running

Select the proper remote auto detected device

Then, when you run (in release or debug mode) your app in VS2015, the app is deployed and launched in the remote device and, as it happens when you run it on the Local Machine, your app will be available, on that remote device in the All apps list, even afterwards, till you explicitly uninstall it.

Note that, after created the Package, you can even launch the validation tests on the remote device and if the Windows App Certification Kit is not found there, you can configure it correctly following the wizard displayed on the target device and then the Launch WindowsApp Certificate Kit button became enabled and you can run the certification test on the remote device where you agreed to install the Windows App Certification Kit:

Validation tests on the remote device

Run validation on remote device

After accepted on the target remote device the installation of the Kit, the button becomes enabled

Installation on the remote PC

Installation on the remote PC (2)

Running the certification toolkit on the remote PC

See also: Enable your device for development, Downloads and tools for Windows 10, Creare un pacchetto di app and Publish Windows apps