Twitter for iOS has been updated to version 7.33 which brings several new features and improvements, including a new Data Saver toggle. You can download the update directly on your device through the Apple App Store or by using the following link:
You can enable the Data Saver toggle by heading to Settings on your iOS device. Once enabled it will be activated for all Twitter accounts on that device. When you enable to new Data Saver toggle it will block videos from auto-playing and provide low-resolution previews of images.
Additionally, the update also brings additional controls for group messages that introduce a simpler way of controlling who is in a particular group. The update also includes improvements to VoiceOver poll interactions and better labels for certain types of ads.