When comparing AppTrap vs Virtual Box, the Slant community recommends Virtual Box for most people. In the question“What are the best Mac OSX apps for someone that's new to Apple?” Virtual Box is ranked 15th while AppTrap is ranked 18th. The most important reason people chose Virtual Box is:
It works for Windows, macOS, Linux, BSD, and many others.
Ranked in these QuestionsQuestion Ranking
Pros
Pro Prefpane style app
AppTrap installs a daemon that runs in the background monitoring the trash, when you drag an app to the trash it will search for associated .plist files that have been left behind and ask to move them to the trash. In other words, AppTrap launches and does the work for you automatically. All you have to do is uninstall apps the old fashioned mac way by dragging apps to the trash.
Pro Compatible with Many Operating Systems
It works for Windows, macOS, Linux, BSD, and many others.
Pro Beginner friendly
A virtual machine can be set up in minutes if a ISO file to load is already available.
Pro Works well and fast for Windows host and Linux guest
Pro Free and open source
Pro Many free images available
Though most are linux flavors at https://virtualboxes.org/
Oracle's virtualbox site has others.
Pro Can do snapshots
Pro A lot of customization
VirtualBox has multiple virtualization options. Each one may be tailored to the guest operating system’s needs. This makes it especially good on virtualizing older systems, such as DOS, obscure distros, etc.
Cons
Con Not Supported in Big Sur
Con Gets some things, not everything
This is thorough enough in cleaning up most of the cruft that gets left behind by applications, but might not get everything for the more invasive applications, especially if some of the files have privileged permissions.
Con Requires using Finder
Does not work if you trash app using alternate file browser like Path Finder.
Con Lacks video performance
Virtualbox has a hard cap of 256MB of video memory. This could make newer operating systems run slower.
Con Minimal CPU customization
You can only enable/disable certain features. You cannot cap the speed of the CPU, which is required to run systems such as Windows 95.