The last time I evaluated these for use in my app, I found that the "consistent" and "minimalist" visual style makes it really difficult to recognise object/plant/food emoji from one another by shape or at a distance. Other emoji have clear shapes, but not enough internal detail to understand what they mean. this is especially problematic with a set of non-Android, non-Twitter, non-Apple emoji, where users haven't <i>learned</i> the shapes yet, but have to go by looks. It looks like the creators of this project wanted "function over form", or at least "form follows function", but in their pursuit of Bauhaus they accidentally ended up with Droodles.