These are top and recommended SMS Notification Extensions For Magento Ecommerce:

1. Landofcoder SMS Notification Extension for Magento 2
It is the most optimized and convenient way for you to interact quickly and directly with your customers through SMS that helps to send and receive short notification messages. Landofcoder Magento 2 SMS Notification extension is an ideal & powerful module that enables you to send SMS Service API with Twilio, BulkSMS ­­­­­­­­­to your customers whenever you offer various events in your Magento 2 store. Moreover, it only takes few seconds to transfer notification & easy customization. Be an intelligent businessman, choose Magento 2 SMS notification with some outstanding features below:

Link: https://landofcoder.com/magento-2-sms-notification-extension.html

2. MageComp Magento 2 SMS Notification Extension
Magento 2 SMS Notification Extension provides facility to notify customers about various order status activities through text messages.
Reward Points You will earn 5 MageCoins for writing a review and 5 MageCoins for rating this product.

Link: https://magecomp.com/magento-2-sms-notification.html

3. Vnecoms SMS Notification Extension for Magento 2
SMS Notification extension for Magento 2 is a comprehensive and powerful module that enables you to send SMSs to your customers or administrators during various events in your Magento store.

Link: https://www.vnecoms.com/magento2-extensions/magento2-sms-notification.html