I'd love to be able to quickly reference my players' sheets at a glance rather than opening them fully. 

Why this would be helpful:

• Prepping for sessions to see their HP, available spell slots, resources (making this customizable would be great too, see below)
• Check their Passive stats (I've made myself a printed cheat sheet, but this would be helpful)
• Languages, other skills that often fall into, "Who knows/has X?" and then everyone looks at their sheet

Customizing:
We don't need to see everything (and probably shouldn't), but certain selectable aspects would be great

• HP remaining/Max HP
• Available spell slots - not what spells they have prepared; that's for them, but how many have left should the DM feel benevolent 
• Consumables such a health potions - again, how are they doing on resources
• Limited use items and traits, like Rage or uses on commonly used items - this may feel like micromanaging, but who can remember between sessions how many times the barbarian raged in the heat of the moment?

Just an idea I had today while prepping for a session tonight. Thanks for the space to make suggestions!