I have used lots of alternative email apps and I found CloudMagic is very powerful and user friendly no matter in functions or visuals. It has clear and simple designs, ux flows. It works on different platforms like Mac, iOS, Android. CloudMagic can share team contacts, as well as integrating with other productivity apps such as keynote, Outlook notebook. Other very useful function is it allows you to get and reply Gmail emails in mainland China where we all know that gmail is blocked.
But after using it for a very long time, I found that iPhone version Cloud Magic doesn’t support Chinese language reply. You can get emails in Chinese, but you can only type in English when you reply it on your phone. But for non-Chinese speakers, it didn’t really matter. But once I need to translate some emails into Chinese and send it back, then I found I can’t type in Chinese on my phone app.
I started to discover another email app: Spark. It is featured in Smart Inbox, which can filter your emails into different categorizes, and this app allows Chinese replies on phone. Another feature is Snooze and Task, you can put your to do list and set notification time to remind you. It is very customizable, widgets and swipes can be personalized to match user’s work flow.
Those are two email apps that I recommend to try if you are looking for alternatives.