Tomáš Rychnovský has posted a great little new tutorial on getting the most out of Bitmap Fonts in Phaser: "Very often I need to display some information for player in GUI in my games. It is usually composed of some text and icon. And it also often takes some time to fine tune positioning of text and icon. Things can get complicated quickly."
This tutorial guides you through merging Sprites into your Bitmap Font, so you can render them in-line with the rest of the text without worrying about coordinate placements or text widths.