How to create USSD application ?
We have heard about USSD. It is a basic service supported on all gsm phones and gsm mobile networks. USSD is the only way to tranfser data from user to the network and without internet in real time. Many service providers provides application accessibility from internet and USSD both. E.g in countries where internet is not available at all places, ussd enables to access same service without internet. In previous blog we have discussed lot of about ussd internals. Here we will cover what is an ussd application and how to develop.
What is an ussd application?
Like many other applications , it serves a purpose. You might have heard about voting. A voting can be done by sms (just sending your option to a short code) or via ussd (dialing a code or string and select and option from a menu displayed). The main thing in an ussd application is the menu. A menu depends on the application logic. E.g you might need to vote a candidate in your area via ussd. In this case a menu will have list of candidates and you will choose one or may be none. Once chosen , the next menu is just the display of status (successful). Facebook also and application which can be accessed via ussd.
How to develop an ussd application?
Now we know ussd and an application over ussd. So next what we need to do to develop an ussd application? First thing is communication with the device. This is only possible via mobile operator or aggregators , who connects to mobile operators and give connectivity to others. Once you find any one of the option, next comes a string , which a mobile user will dial and will access the service. This string should be published on mobile networks for routing of ussd message towards your application. Now connection is set , next, what protocols need to be handle? The protocol is GSM-MAP 09:02 over SS7. You can directly use the ss7 stack and build the application logic in application over ss7 stack. Or other is use an USSDGW. With USSD gateway you need to use simple and easy APIs to develop you business logic.
One all done test ussd application with the real device and make available for others.