Aqua Mail

AquaMail is a new email app for Android 2.0 and higher.
Easy automatic setup for popular email services (Yahoo, Hotmail, Gmail, and more).
Support for many other email services via standard Internet email protocols: IMAP, POP3, SMTP. This includes many corporate email servers, such as Lotus Notes and Exchange, provided that the administrators enabled IMAP/SMTP.
Push mail (IMAP IDLE, instant incoming email delivery) for those servers that support it (Gmail, GMX and more).
Plays well with other email programs that you may be using to access your IMAP mailbox. Uses existing folder structure, can synchronize drafts, sent, and deleted messages.
Can save attachments on the memory card.
Widgets (message counts, message list).
Tasker integration (change settings, trigger mail check).
Lots of settings to configure the application just the way *you* would like. Separate settings for WiFi and mobile connections.
This is the Lite version, which is limited to two accounts, no identities, and adds a promo signature to all outgoing messages with a link to the program’s web site.