1) SIM Browser or SIM Application Toolkit (STK): This option is probably the most popular since it is quite secure, offers good usability, and works well on low cost handsets. An application is programmed onto the SIM to present a menu to the user and obtain the user's input. Transactions are usually passed through encrypted SMS. This option is only available on GSM networks and usually requires swapping the user's SIM for one with the application on it.

2) Mobile Internet: Uses GPRS, 3G etc. for communication from the handset to the mobile money platform. This option is not very feasible when mobile internet channels do not cover the entire network or in areas where the penetration of mobile internet enabled handsets is low.

3) Structured SMS: This option is a very simple and straightforward implementation involving a direct connection between the mobile money platform and an SMS gateway. Standard SMS messages are used to transmit the mobile money transactions which means no specific application is required on the handset or the SIM. Bulk carriers can be used to manage connectivity to multiple mobile operators and this technology can be deployed on GSM and CDMA networks, making it quite flexible. However, structured SMS is a lot less secure than other options and can present some usability challenges since it is not menu driven.

4) USSD (Unstructured Supplementary Services Data): This is a standard for transmitting information over GSM signaling channels and is mostly used as a method for querying the balance in a pre-paid GSM service. USSD is usually faster than SMS and does not require any application to be installed on the handset or the SIM. However, this channel requires the mobile operator to have a gateway that is compliant with USSD Phase 2 (specified in GSM 03.90)

5) JAVA (J2ME): A JAVA application is programmed and installed on the mobile handset and then SMS or Mobile Internet is used to communicate between the handset and the mobile money platform. This option is not very feasible for markets where there is a high penetration of low cost handsets since many of these do not support JAVA. Also, most of the time the JAVA application will not be compliant with all handset models.

In summary, the following table outlines the trade-offs between the options described above: