This requires that you have a server at which you can save a document accessible via the internet. If you have Dropbox, for example, the public folder will do.
Create a new text document containing nothing but the value of the latest version of your program. E.g '23.4'.
Save the document with an html suffix in your public folder, such as 'latestversion.html'.
Copy the public address of the html document. E.g. 'https://YourAddress.html'.
Put this into your opening function:
% This program version:
ThisVersion = '1.3';
% Get the latest version from the html document:
[NewVersion,status] = urlread('http://YourAddress.html');
% Check if latest version is newer than this version:
if status~=0 && str2double(ThisVersion)<str2double(NewVersion)
msgbox('There is a new version available.', 'Note');
end
If the value specified in the html-document is larger than the value of ThisVersion, specified in the program, a message box will be opened informing the user about the new version. Make sure to update both the value of ThisVersion and the value in the html-document when making a new version of your program.