I have noticed when I tap the “Quick add to inbox” on my Android lockscreen, i am then prompted to unlock my phone. Upon doing so, the quick add bar does not appear.
However, if my phone is unlocked, and I press the same, then the quick add bar appears.
Its not a big issue, but just wanted to flag as it may be a bug with the app, and does at time slow me down a tad when I want to add something quickly.