With Mailplane, you get Gmail, Google Calendar, and Google Contacts - all in the same application. Simply put, Mailplane is a native Mac app that wraps around the familiar web interface of Google’s products. If you have multiple Gmail accounts that you use simultaneously, Mailplane is the app you need to have on your Mac. Gmail for mac free download - SysTools Mac Gmail Backup, Gmail, Gmail, and many more programs. The icon allows access to gmail and calendars, via my google account. While they did discontinue the product and the numbered notification function in Notifier, I was able to use Notifier preferences to disable the automatic features yet still use the icon in the main Menu to still access my logged-in Gmail account. And I had locked the application prior to announcements of its demise. Neither of these were suitable for my older Macs (pre Snow Leopard) but I already had a Google Notifier version in each of my Macs. Or an add-on to an existing supported browser that could allow you to see gmail when already online in a browser.
There used to be an item known as Gmail Notifier for Mac, and this recently (last week) was discontinued by google citing their browser was their answer.