What does 逆再生ボタン 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 逆再生ボタン?

HTC first drew 逆再生ボタン in Sense 7, released 2015年3月30日.

HTC Corporation has shipped 2 versions of 逆再生ボタン. Each is dated, so you can see when the design changed.

HTC

HTC Corporation has drawn 逆再生ボタン 2 times. Every revision HTC has shipped is below, newest first.

What does 逆再生ボタン 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 逆再生ボタン?: HTC first drew 逆再生ボタン in Sense 7, released 2015年3月30日.
How many times has HTC redrawn 逆再生ボタン?: HTC Corporation has shipped 2 versions of 逆再生ボタン. Each is dated, so you can see when the design changed.

HTC artwork for this emoji spans 2015 to 2016.