K-9 Mail client is simply the best and the most versatile way of working with your inbox on the phone. I've been using it since 2009 on a number of Android devices and never had any issues with the app. Extremely fast  reliable and configurable  doesn't drain battery even with the frequent push-notifications enabled  has intuitive interface  and does exactly what it has to do. K-9 Mail is also smart enough to recognize necessary settings for the majority of ISPs  making the initial setup effortless. Thank you guys for this decent open-source software.
July 26 2016