To use Siri with Microsoft To Do, you just need to connect your personal or work Microsoft Account to the Apple Mail, Calendar or Reminders app.
To connect your personal Microsoft Account, just head to your iPhone's settings, select either the Mail, Calendar or Reminders app. Then just tap Accounts > Add Account and select Outlook. Follow the prompts to log in and connect your Microsoft Account.
To connect your work Microsoft Account, just head to your iPhone's settings, select either the Mail, Calendar or Reminders app. Then just tap Accounts > Add Account and select Exchange. Follow the prompts to log in and connect your Microsoft Account.
Once your Microsoft Account has been connected, you'll need to set your default Reminders list to one in your Outlook or Exchange account. Just open your iPhone's settings, tap Reminders > Default List and then select the desired list.
Now you can simply say 'Hey Siri, remind me to...' and it will be synced to Microsoft To Do. Please know, however, that Siri does not currently work with business customers who are using InTune.
