Although not really an SMS gateway, Pushover performs a similar function. Message recipients will need to have the Pushover apps installed on their iOS or Android device. One of the advantages of using Pushover is that you can send messages to any mobile device that has an Internet connection (eg. phones and tablets). The device doesn't have to be a phone..
You will need to complete the settings on this screen if you are using Pushover to send PhonePad messages to mobile devices.
If you don't have an account with Pushover, you can open one (it's free) by visiting their website. Details are available here.
These are the details of the sender name and email address that MessageSender will be using to send the text messages.
Testing Your Settings
Click the Test button to test your Pushover settings. The following screen will be displayed:
You will need to enter a Device Name. This is one of the devices registered under your Pushover account. The device will need to have the Pushover iOS or Android app installed to receive the test message.