Agile Tortoise's Drafts has revolutionized iOS in its ability to quickly send text from one place to the next. It's clean, fast and it lets you get back to work. Hon Cheng and Junjie have brought a similar sophistication to email with Dispatch for iPhone.
In my experience, the majority of email that flows through my inbox has to leave not in the form of a response, but as an action. Actions in this case are defined as anything that needs to be somewhere else, either in the form of a todo, an item on a list, or a piece of reference material in a context outside of an inbox. The challenge of implementing a system like this on iOS is balancing power with simplicity. Dispatch's clean and minimalist design presents you with only the elements you need like and keeps everything else safely tucked away to the left ala Gmail
Dispatch was built around Merlin Mann's Inbox Zero which stresses the importance of Process and deciding what actions need to be taken to get that email out of the way.
Admit it, most of the email that you get you would be better off not ever recieving in the first place. To that I recommend unsubscribing from the myriad coupons and alerts that you unwitingly signed up for over the course of your life with email. Do it. For everything else, a partial swipe to the left shows a panel of actions you can take (mark as unread, star, etc.) while a full swipe quickly archives that email and moves you to the next one.
I'm slowly learning that there is no single system that can do everything that I want. I use Fantastical for Calendaring (although Cal from Any.Do looks enticing), Omnifocus for tasks and projects, and Listacular for lists. Switching between all of them though can be confusing and time-consuming and that's when Drafts and Dispatch become invaluable tools for reducing friction. Different emails require different actions. Currently supporting 14 apps, email content is quickly transferred to a place that makes sense for it to go as a task, an event or what have you.