dt's tutorial is good because it also allows retrieval of release notes and such all in one go. The tutorial is great, but it does this all just to ultimately check the version number in the end whereas so much more could be done (as he does in his actual scripts) using the extra data.
For simply retrieving version number something like Stigmata's code is fine although I personally use a PHP script. The Plus script requests page (www.whatever.com/version.php?name=Plus!Mail), the PHP script then retrieves the appropriate latest version number from database and returns it.
I like this method because it allows multiple scripts to be checked using the same system and a single URL (with a different 'name' parameter).
Either way, good job on releasing this tutorial dt. Glad to see people focused on helping others
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