K-9 Mail is one of the most comprehensive email clients out there for Android devices, rivaling even some of the more famous paid apps.
Among some of the features available with the application include the ability to synchronize various accounts and email addresses, label emails with different tags, archive selected messages, create signatures, and store data on your SD card.
The application will also display alerts and notifications for each of your accounts or separate folders. This is all completely configurable, so that you'll only be alerted about whatever you deem important.
K-9 Mail is an easy client to control, simple to manage, and packed with high-quality features. Sending email messages (with or without files attached) is a breeze with this client.