When comparing Avalonia vs MonoDevelop, the Slant community recommends MonoDevelop for most people. In the question“What are the best free cross-platform (mobile and desktop no web) app development frameworks that can be used to create commercial apps?” MonoDevelop is ranked 2nd while Avalonia is ranked 3rd. The most important reason people chose MonoDevelop is:
MonoDevelop is free to download and use.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Open source
Pro UI designer plugin
A User Interface designer plugin for Visual Studio can be downloaded from the Visual Studio Marketplace.
Pro Free
MonoDevelop is free to download and use.
Pro Starting up this program doesn't take as long as starting Visual Studio windows 98
Cons
Con Beta
Still in beta status.
Con No longer supported (deprecated since 2018)
Starting with version 4.x, Xamarin rebranded MonoDevelop as Xamarin Studio, but only for the Windows version of the IDE.
Stable release
7.6.9.22 / September 21, 2018
Con Bad formatting
MonoDevelop doesn't offer much in terms of autocompletion and code formatting. Most of the time the automatic formatting that MonoDevelop does is annoying and not really compliant with C# guidelines.
Con The MonoDevelop version that ships with Unity is several versions behind
The version of MonoDevelop that ships with Unity is several versions behind the main MonoDevelop branch. It also gets updated very rarely so any annoying bugs that it may have take a lot of time to get fixed.