Kiwi for Gmail is an excellent app that brings Gmail and Google apps directly to your desktop.

Choose your view based on Date, Importance, Unread, Attachments, and Starred. Or combine filters to create a shortlist of your most relevant emails.

An intuitive new toolbar on the left side of the traditional Gmail interface provides quick access to all G Suite applications and documents.

Send huge attachments — the simplest and quickest way to send big files.

Finally, a solution for office productivity that competes with Microsoft Office 365; use Google Docs, Sheets, and Slides as native, windowed desktop applications within Kiwi for Gmail.

Even restore the windows you had open on restart. Plus, it works seamlessly across all your accounts.

Open documents in their windows so you can multi-task like never before using documents across applications and accounts.

One of the great things about Gmail is third-party plugins. They have added support for Boomerang, the most requested plugin, and will be adding more in the future.

Limitations:
For a limited time, you can get 100% off the first year using code KiwiForFree