Being able to handle your email in an efficient manner is critical for worker productivity.
There is a nice array of powerful email clients (apps) that run on your computer or mobile device to help you stay on top off all that email.
Be sure to check out these options:
K-9 Mobile Mail App for Android Devices
Thunderbird with Lightning calendar (by Mozilla)
The BAT, a high security email client for Windows computers
a legacy tool, but worth a look is
Pegasus / Mercury