it seems like .mlapp not compatiable or has changed since version 2023a and I am not sure what kind of promblem it is.

.mlapp seems to be a Matlab-specific format, not a normal text format, which makes it impossible for me to copy it to other computers (running different versions of Matlab) at will.

Is there any information about compatibility between APP designer versions? I cannot accept the incompatibility of "source code (in binary format)".

it seems like .mlapp not compatiable or has changed since version 2023a and I am not sure what kind of promblem it is.

.mlapp seems to be a Matlab-specific format, not a normal text format, which makes it impossible for me to copy it to other computers (running different versions of Matlab) at will.

Is there any information about compatibility between APP designer versions? I cannot accept the incompatibility of "source code (in binary format)".

• matlab
• matlab-app-designer

• 1 If nothing else works, you can recover the code from the .mlapp file, this way (make a backup copy before): change the extension of the file from .mlapp to .zip then unpack it in a folder. Explore the folders, you can find the MatLab code in the folder "matlab" (it is a xlm file, remove the uncecessary text), a picture of the GUI in the metadata folder and so on. – il_raffa Commented Jan 21 at 8:19
• 1 There is also an "export code to mfile" option within the SaveAs menu which makes @il_raffa's suggestion a bit simpler if OP can re-open the app in the original version of their app – Wolfie Commented Jan 24 at 8:18

1 Answer 1

MLAPP files provide forward-compatibility, but don't guarantee backward-compatibility. New functionality has been added to App Designer in basically every release since it was introduced, and new functionality will inherently not work in older versions of Matlab.

If you want to ensure you can use an MLAPP file in multiple different versions of Matlab, it needs to be compatible with the oldest version that you intend to use.

To achieve that, you can either (1) create the app in the old version of Matlab or (2) open it in the version it was created in, and use "save as" to save it for compatibility with the old version. You must make sure the app does not use any functionality not supported in the old version (for example, if it uses uitree then you can't use it with any version prior to 2017b).

https://www.mathworks.com/help/matlab/creating_guis/compatibility-between-different-releases-of-app-designer.html

https://www.matlabsolutions.com/resources/will-my-app-designer-app-be-compatible-in-previous-and-future-releases-.php

As others indicated in comments, MLAPP files are effectively ZIP files with various content inside, similar to Microsoft Word DOCX files. But that doesn't really affect your problem.