On LG G2 you can change the conversation theme, to change the background wallpaper and bubble styles when texting friends. You can also have different themes for each conversation (each contact).
To customize conversation theme, do as follows:
1. Open Messaging application
2. Press Menu Button and then go to Settings.
3. Tap Conversation theme.
4. Now change the wallpaper, from default options or from Gallery or Camera
5. Go to Bubble tab to change the bubble style
** To set a theme for a specific conversation, open the conversation, go to settings > conversation theme, and change the background and bubble style
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