Best email app I have used for work emails , it has read email option so know they have read your emails even if you haven't requested a read receipt. Also the format is brillant love every bit of it :-)

Canary Mail does a great job at consolidating inboxes, and giving the user more customization than other apps, e.g., swipe gesture customizations. The simple interface, mimicking the default iOS Mail app interface, is easy for a user to pick up and use. When it worked for me, the read receipt functionality was nice.

Easy to set up and use. Looks a lot like the native client. Easy to get the hang of.