Getting lots of people to use your virtual assistant means it needs to be easier than if they were to just do it themselves. Amazon was able to find success with Alexa for being one of the first with a smart speaker on the market, but also because they were able to sign up so many 3rd-party developers to the platform. Google Assistant can do a lot of the same things, but many will say it doesn't have enough 3rd-party developer support. Google has been working to integrate popular messaging services and have recently added read and reply support for Telegram, WhatsApp, and Slack messages.
Google Assistant has been rather barebones when it comes to reading and replying to any message that weren't sent to Android's stock Messages or the Google Hangouts applications. If you used anything else, issuing a command like "read my messages" would completely ignore anything sent to you over even the most popular messaging applications for Android. This meant anything sent from applications including WhatsApp, Telegram, Slack, Facebook Messenger, Signal, WeChat, and many others were simply ignored by the Google Assistant.
It seems some people within the Android community have noticed a change in how Google Assistant interacts with these messaging platforms. We haven't heard of any official announcement from Google, but tests have shown that asking the same "read my messages" command now has Google Assistant reading out messages from applications including Telegram, WhatsApp, and Slack. Not only that, but you can even reply to these messages just like you would reply to SMS text messages before.
You'll know when this feature is working on your device because after issuing the "read my messages" command you will see a prompt appear that asks you if you want to let Google Assistant have access to your Notification data. That's the only way Google Assistant is able to read these messages to you, it's simply accessing the notification data (not going into the app itself). Therefore, if a message contains images, videos, or audio then the Google Assistant will say "the message just contains an [media type] attachment" and won't be able to play or show it to you.
Still, it's nice to see Google finally expanding this support to more messaging platforms.
Via: Android Police