What does Bouton Retour look like on HTC?

On HTC it is the design shipped in Sense 8, shown above at full size. Older revisions are listed beneath it.

When did HTC add Bouton Retour?

HTC first drew Bouton Retour in Sense 7, released 30 mars 2015.

HTC Corporation has shipped 2 versions of Bouton Retour. Each is dated, so you can see when the design changed.

HTC

HTC Corporation has drawn Bouton Retour 2 times. Every revision HTC has shipped is below, newest first.

What does Bouton Retour look like on HTC?: On HTC it is the design shipped in Sense 8, shown above at full size. Older revisions are listed beneath it.
When did HTC add Bouton Retour?: HTC first drew Bouton Retour in Sense 7, released 30 mars 2015.
How many times has HTC redrawn Bouton Retour?: HTC Corporation has shipped 2 versions of Bouton Retour. Each is dated, so you can see when the design changed.

HTC artwork for this emoji spans 2015 to 2016.