I'm thinking of making simple mechanism that checks current core version of elgg and notifies admin in admin panel, that new version is available. Nothing too fancy, but encouragement to upgrade to the new version (why upgrade when everything works...).

I'm not aware of any existiong api to check current version of Elgg. I'm inspired here by Zend Framework that has even special class for version checking. We could think of:

• making page returning "recommended" version similarly to ZF
• use Github api similarly to ZF
• extracting version from elgg.org page or http://elgg.org/previous.php

I'm leaning towards making sth using github api, but "recommended" version would make things easier when it comes to handling RC versions and separate branches. We could utilize community page REST API for this, though it seems overkill for that simple task. Any better ideas?