The official Twitter application for Windows Phone has never been good enough compared to the third-party apps, but the latest update adds one feature that none of the others have: REAL push notifications. You instantly get notified of new mentions, favorites, retweets, direct messages, or new followers. The settings page let you individually turn on/off any of these.
Some third party Twitter apps on Windows Phone don't even have push notifications at all. Some have delays of a few minutes before you actually receive notifications. The official one is instant.
While push notification is great, the official Twitter app isn't for super users. It still doesn't have "reply to all" or thumbnail previews. It also isn't accessible through the sharing option via the photo album.
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