There are two types of dictation activities: TEDICT and TEDICTisy. You can also just watch the video with subtitles. First, choose which TED Talk you want to do. Start by browsing the Newest Releases. The times are included, which is very helpful.
Here’s TEDICT with the language setting in English. You listen and type what you hear:
Not very useful this way. But you can change various aspects of the settings, to see/hide the translated text while dictating, for example.
And here it is with the language setting in Japanese (it’s a different TED Talk, but you get the idea):
The TEDICTisy is slightly different. The words are in random order at the bottom, and you have to click on them in the correct order. Here’s an example:
There’s also a vocabulary page, which will give you some minimal information about the words that appear in the TED Talk you’re listening to:
This app will be useful for your English listening, and it can also be useful for other languages you’re learning. Try switching the language setting to German, or Korean, or Chinese to learn some new vocabulary or review words you’ve already learned.