"The rate limit is imposed by Twitter. It's related to the rate that data is pulled into the app. All third party Twitter apps (basically any Twitter app that isn't the native Twitter app or TweetDeck, also owned by Twitter) are limited in the amount of data calls they can make to Twitter's API."
I used to get similar whilst fonefagging (not the rate limit msg though) - I just used to change mobile. to www. in the URL and it'd load fine…