What does Thought Balloon 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 Thought Balloon?

HTC first drew Thought Balloon in Sense 7, released March 30, 2015.

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

HTC

HTC Corporation has drawn Thought Balloon 2 times. Every revision HTC has shipped is below, newest first.

What does Thought Balloon 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 Thought Balloon?: HTC first drew Thought Balloon in Sense 7, released March 30, 2015.
How many times has HTC redrawn Thought Balloon?: HTC Corporation has shipped 2 versions of Thought Balloon. Each is dated, so you can see when the design changed.

HTC artwork for this emoji spans 2015 to 2016.