Install developed Application without developer mode

Sideload apps is a more secure option than Developer mode because you cannot install apps on the device without a trusted certificate.

Requirements

Here's what you'll need to have:

• Devices need to be unlocked for sideloading (unlock policy enabled)
• Certificate assigned to app
• Signed app package

And here's what you'll need to do:

• Turn on sideloading - you can push a policy with an MDM provider, oryou can use Settings.
• Trust the app - import the security certificate to the local device.
• Install the app - use PowerShell to install the app package

How do you sideload an app on desktop

You can sideload apps on managed or unmanaged devices.

To turn on sideloading for managed devices

• Deploy an enterprise policy.

To turn on sideloading for unmanaged devices

• Open Settings.
• Click Update & Security > For developers.
• On Use developer features, select Sideload apps.

To import the security certificate

• Open the security certificate for the appx package, and selectInstall Certificate.
• On the Certificate Import Wizard, select Local Machine.
• Import the certificate to the Trusted Root Certification Authoritiesfolder.

To install the app

• From the folder with the appx package, run the PowerShellAdd-AppxPackage command to install the appx package.

Source: https://technet.microsoft.com/itpro/windows/deploy/sideload-apps-in-windows-10