As off late it's been issues sending attachments via email with the app . Either failed are goes to outbox as being Quied in progress of sending but immediately fails going on like this for a long time. Web version works fine . And it's not my phone I rechecked with another phone same issue please fix this. I usually send documents via email saves time going to the post office to post them out .. the longer the email you write has same issues. I have been using Gmail for over 15 years now