Detail this asset from Unity Store: Original Link
This is a paid asset, but now you can download xARM: Aspect and Resolution Master Free.
xARM Aspect and Resolution Master v1.8.2
New: Unity 2019.1 support added
xARM is the powerful and easy-to-use solution to get a real preview of your game.
– Preview at device’s physical size
– Verify pixel perfectness
– Compare multiple resolutions while editing
– Batch screenshot export
“you’d be thankful you got this in your toolbox. Must buy asset!” – user review
No need to build to a device only to check:
– Is the GUI usable at resolution xy?
– What is the physical size of a button?
– Do the atlases switch correctly?
– Does the translation fit into its space?
– How does a change effect other resolutions?
– Does the player exactly see what was intended?
– …
With xARM you see everything at a glance.
No need to be daunted by display fragmentation.
xARM yourself.
More info: Video Preview | Forum | User Guide
Features:
– Covers all relevant devices of:
iOS, Android, Windows Phone 8, WinRT & Standalone
– Preview at physical size and pixel perfect
– Get an overview of resolution popularity, etc.
– Supports uGUI & ALL other extensions
(e.g. NGUI, …)
– Export screenshots as PNG files
– Huge time and trouble saver, will pay off soon
– No or minimal coding required
– Full source code access (C#)
– Supports Unity & Unity Pro (2019.1, 2018.x, 2017.x & 5.x)
– Much more…