Google updates Gmail for Android with add-ons to help users be more efficient
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Since the add-ons are now available on both Android and desktop, it will be enough to install them on one platform – you'll be able to access them from all your devices. In order to get started with add-ons, you must tap on the settings wheel on the top right of the Gmail inbox and choose the “Get add-ons” option.
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Here are just some of the add-ons that you can start using with Gmail today: Asana, Dialpad, Hire, Intuit QuickBooks Invoicing, ProsperWork, RingCentral, Smartsheet, Streak, and Trello. Many more add-ons are expected to be released in the coming months including DocuSign, an add-on that will allow you to sign contracts, agreements and other documents directly in Gmail.
If you're using G Suite or Gmail on your desktop, then you can find these add-ons in the G Suite Marketplace. Once they're installed on your PC, you'll be able to access them from your Android devices as well.
source: Google, G Suite Marketplace
Things that are NOT allowed: