You can receive notifications in the HubSpot mobile app for sales activity, mentions, and tasks.
HubSpot Sales tries its best to send notifications to where you currently are. If you've turned on notifications in the mobile app, you will receive push notifications to your phone by default between 8:00am and 10:00pm unless you're at your computer. If you're at your computer and can receive real-time notifications, they will appear in the top corner of your desktop and you will not receive a push notification on your phone.
You can turn off notifications for sales activity, mentions, and tasks in the HubSpot mobile app Settings under Notifications.