Compliance stuff isn't a nice-to-have feature. The LGPL provides no exceptions for beta releases. However, the LGPL is technology-neutral and does not directly require you to implement a GUI.
You must reasonable notices about the open source components that you use. How to do this depends on the nature of your software.
For a graphical application: Moving license notices to a separate screen or file is fine if the user has the actual ability to access these. I'd have doubts about that for a mobile app, though it's probably fine in a desktop context. In essence, I would expect this test case to pass:
Given that I am an end user
And I am on the copyright notice screen
When I click on the license notice link
Then a window with the license notices appears
In a mobile context, showing a plaintext file with a web view is probably the easiest way to get this done.
It's worth emphasizing that you must provide the license notices alongside the app. Unless this is a web app, it's not sufficient to load the license notices from a web server. This should work fully offline.
For a non-graphical application: If the software provides an interactive user interface (e.g. a REPL or command line) then it should show a short message about license information to the user. For example, the GDB debugger is a GPLv3 program that shows the following message upon starting:
Copyright (C) 2021 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
Type "show copying" and "show warranty" for details.
(With respect to notice requirements GPLv3 and LGPLv3 are generally equivalent.)
If the software is non-interactive, you don't need such notices. It would likely be sufficient to include the license notices in a file, but to inform the user how to find this file. That means, I would expect the license notices to be part of the included documentation files that are shipped with the program. E.g. if you release your software as a ZIP archive that users can unpack, having a LICENSE file in the archive would be an obvious way to store such information.
The LGPL also requires much more than just showing the license notices. You must offer the source-code for the LGPL-covered components. You must make it possible for the end user to modify the LGPL-covered components. In a desktop context, this is most easily achieved by distributing the LGPL-covered component as a separate library (e.g. DLL on Windows).