How to use Siri with Twitter? It’s easy. To be able to send tweets with Siri, or make Siri search for Twitter hashtags, navigate to Settings > Twitter on your iPhone, and add your Twitter account details. Now you can have Siri send your tweets for you!
This is where you fill in your Twitter account information.
This is where you can add more Twitter accounts.
If you want Twitter user names and photos to be added to your Contact cards, select this option.
Allow These Apps…
Here you’ll find the iOS apps that have been granted access to your Twitter account details.