One of the problems with Gmail for me has been that I couldn't access my account with my Pocket PC or Smartphone, since Gmail required functionality Pocket Internet Explorer couldn't offer. But from today Gmail is rolling out POP3 access to their accounts, and that is good news for your Smartphone. This rollout will be done gradually, so your account may not have it yet, but happily mine did. First you need to enable POP access in your account settings.

As you can see, you get to select if you want to keep your messages in your Gmail inbox when downloaded from the POP3 server, or you can choose to Archive or Trash them. After this, you need to setup your email client for the Gmail server (like for example
Outlook). Gmail can help you by doing this automatically for many clients, but for a Smartphone you'd need the manual procedure. The Gmail POP3 access does require a secure SSL connection, but that is no problem for your Smartphone. After setting up my Gmail account in Inbox, and starting the download of my first messages, I did receive a warning that the server certificate was not valid. But I went ahead anyhow and everything went ok. So now I have access to my Gmail account from my Smartphone. YeeeHaaa!