The Google Assistant situation is a huge mess at the moment. There are three different Google Assistants, and each have a specific featureset, which means some things are missing from one of them but not others, and so on. The Google Assistant that's exclusively built into the OS of the Pixel and Pixel XL phones can only take commands via voice - you simply can't write in order to ask it something. On the other hand, the Google Assistant that lives inside the Allo chat app can be talked to or texted, but only replies via text and never speaks to you. The third Google Assistant is the one you...
Source: http://www.gsmarena.com/the_pixels_google_assistant_is_getting_keyboard_input_soon-news-22598.php
