The USSD Portal platform module enabled Play Mobile to quickly roll out new USSD services. The solution allows Play Mobile staff to create arbitrary USSD menus, query external services, build dynamic menus, and much more.
The SMPP and SIGTRAN protocols are used to connect to mobile network operators.
Sometimes, SIGTRAN connection is mandatory for mobile operators to be able to implement USSD services because they don't have a USSD gateway or the gateway is limited. This removes the need for mobile operators to buy new hardware or additional licenses.
With SIGTRAN, you can bypass the limits on the number of connections to the USSD portal. It also enables you to more flexibly manage traffic, for example, USSD session timeouts. This is extremely important for payment services where a subscriber may need to enter a long code. In addition, SIGTRAN connection increases fault tolerance as a whole.
The use of USSD services is very important, since mobile Internet coverage in Uzbekistan's regions is uneven. There is stable reception in major cities, while in other parts of the country, the situation is different. USSD queries work instantly, you only need a phone (supported on all existing GSM standard phones). The queries do not require an Internet connection, they are available in roaming and even when your account balance is negative.
Upon request by Play Mobile, we created a range of USSD services for the banking sector: a service was launched for UzCard, for the National Bank of Uzbekistan, the Uzbekistan's largest bank, as well as solutions for other banks in the country. These services allow subscribers, through USSD, to pay for various services, make money transfers, check balances, and personalize their profile.
A remarkable feature of the USSD service for UzCard is that it is also used by the UzCard mobile app in cases where there is no Internet access, i.e. the app uses USSD as a backup channel.