When comparing BlitzMax vs GDevApp, the Slant community recommends BlitzMax for most people. In the question“What are the best 2D game engines?” BlitzMax is ranked 52nd while GDevApp is ranked 83rd. The most important reason people chose BlitzMax is:
You can compile on Windows, Mac and Linux. Nothing to change. There are solutions to compile on the same machine for 2 targets.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Multi target
You can compile on Windows, Mac and Linux. Nothing to change. There are solutions to compile on the same machine for 2 targets.
Pro Modular
There are many modules to extend the features of the language: you can create PDF (via a Cairo module), or just download/upload files (via LibCurl), playing streaming sound (via BASS) and so on (databases, xml, xls...) User can create their own module (they could be written in plain BlitzMax)
Pro Easy syntax
Based on BASIC syntax. Supports OOP, collections (array, list and map)
Pro Stable language and source code
After many years the language it self is very stable. The packages contains the source code of ALL modules (excluding the source of the compiler).
Pro Easy to start, high productivity
BlitzMax is just ready after the installation. Open the IDE, write your code and just press F5 to see the results. You don't need to install other things to use the language. Of course if you want to change the language itself - or modules - you need to install MinGW or other libs, but guidelines are provided and easy to follow.
Pro Fast compiler
With comparison to the some of the other languages Blitzmax compiles source files fast enough.
Pro Compiles to native code
Good performance thanks to native code on each of the target platforms.
Pro Garbage collected language
The language is garbage collected in two modes: reference counting or using the Boehm-Demers-Weiser conservative garbage collector.
Pro GUI for apps
BlitzMax provides the MaxGUI modules that allow to build GUI desktop applications for Windows, Mac and Linux (FLTK or GTK via a module). You also could create your own 'gadgets'.
Pro Great community support
the forum is plenty of examples and solutions! Community is strong and still working, available for getting an hand
Pro BLIde
BLIde is an integrated development environment for Blitz Max, designed to work very close to the project file management performed by BlitzMax engine.
It’s inspired by the .NET IDE and some other great tools, It’s been designed for hobbyist and professional coders.
Pro Quickly add behaviors to objects
Prebuilt behaviors can be added to objects. This is a very efficient way to add a physics engine or make a platformer game.
Lots of behaviors are included, from the most advanced (Physics, platformer, top-down movement) to really simple ones (like the behavior to destroy objects when outside the screen or the one to drag objects with mouse or touch).
Pro Powerful events system to create games without programming
No need for coding using this system which is clear and powerful: events are composed of conditions and actions.
Actions are launched when conditions are fulfilled. This is a very beginner-friendly way of making games and is still efficient for advanced usage, contrary to most other "block"/"drag'n'drop" systems.
Pro Intuitive interface
Pro Based on GDevelop
The entire webapp is based on GDevelop, an open source native game development software available for Windows & Linux, so it benefits from its advanced development.

Pro Can download an archive of the game source
Even though the tool depends on having a server up and running, you can download a copy of your game to run locally, or host somewhere else.
Pro Great UI
Sleek and user-friendly UI.
Pro Can export your game as HTML5 and for Android
Games can be packaged for Android without relying on any third party tool. You can also export your game and download it to host it on your server or let it be hosted on GDevApp.com.
Pro Shallow learning curve
Cons
Con Outdated and abandoned
The author neglected BlitzMax and works on Monkey2.
Con No mobile targets
Only desktop targets available: Windows, MacOS, Linux.

Con Depends on a hosting service
If the website goes down or closes down, you'll no longer be able to develop your games using this system (but you can download a backup of your game from time to time and open it with GDevelop).
Con Cannot deploy native games
For now, games developed with GDevApp can only be deployed for the Web. Android deployment is in the works, but even then, they won't be native since they are built with web technologies.
