[prostoalex]

For one, Sencha's app doesn't allow commenting. For two, it doesn't support notifications, so "re-created" is a generous verb there.

[jlgreco]

Ah yes, comments. One of the hardest things to get right in HTML5. I have never seen it done well, you absolutely need native for that.

[pritambaral]

Sencha's app was a proof-of-concept. Their motivation was to show how and where facebook was "full-of-shit" which they did beautifully. If you read their respective articles, you can discern for yourself.