To display the default keyboard of Android, in most applications, an icon appears with a microphone in its upper right, which allows entering text by voice, dictating it for its transcription into words.
A touch on the microphone is enough for the recognition to start and it is quite complete since even punctuation marks you understand (dictating a comma, period, question mark, etc.); When you press the microphone again, the recognition will stop to transcribe what you have understood up to that point.
Well, although recognition is efficient, it is not perfect and there are few times that you understand wrong things. So, to allow you to quickly correct a misspelled word, the keyboard application has received a change in its interface to include a new delete button.
Yes, it may seem trivial, but when using voice dictation it is annoying to have to switch to the usual keyboard to remove some specific word (s) and switch once more to the voice keyboard to continue the transcription.
In short, what is now added, which many may have already seen or barely consider, comes to solve the above, since it allows deleting whole words with a touch, anywhere in the sentence, and continuing with the input of text by voice. Of course, with this, there will be fewer times that it will be necessary to switch between keyboards.
They comment on Android Police, where they point out this subtle detail, that such a novelty has begun to appear since version 4.8 of the Google app for Android.
More information: Google Help Center