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Pro Easy to use
Mailplane 3 looks just like Gmail's web UI and even imports Gmail shortcuts. If Gmail shortcuts aren't ideal for the user, those of Mac can be used instead.
Pro Can work with mutiple Gmail accounts simultaneously
The tabbed interface included in Mailplane 3 lets users work with as many Gmail accounts simultaneously as they want.
Pro Doubles as a calendar
Mailplane 3 combines Google Calendar and Gmail within a single app.
Pro Supports many plugins
Functionality and features can be extended by using plugins.
Con Gmail only
Mailplane 3 is a Gmail-only client. It does not support other email providers.