Hi - Part of the balance of any customization in Docebo is always the question of, how much do you use the mobile app. The ability to customize there is far more restricted. No global CSS tricks will work or apply, the only real thing in widgets you can impact are within the inside of the widget, for instance in the html widget you can use inline CSS, which limits the CSS techniques and also increases the maintenance level since everything is local. 

Always keep in mind when making a change how much you are essentially creating two user experiences as a result when you make each customization, it often will fall back to ‘just because you can modify, doesn't mean you should.’

Long story short, not really.

That’s such a shame! But I though that might be the case. I’m gonna put in a feature request. The titles are really just for me to know what the heck is on the other side of the widget. My users can see it they don’t need to be told.