Mobile Virtual Network operator (MVNO) Vaya Mobile is now offering 4G services on its post-paid plans, starting from $9 per month.

Vaya's plans go up to $45 per month, which includes 3GB data plus unlimited calling and messaging.

The service piggybacks on the Optus network, with coverage advertised for 97-percent of the Australian population. 4G coverage is much smaller, of course, with service in most of the capital cities.

The fine print

The post-paid offer operates on a month-to-month basis, letting customers cancel after each billing cycle. This is common with MVNOs, like Amaysim, whoi offer a similar deal.

There is one catch in the Vaya small print, though. The telco charges $20 for a SIM pack, which other usual give away or sell for a nominal sum. This equates to two-months worth of service for those signing up to the $9 plan, though the fee is waived if you agree to a 24-month contract with Vaya.

Excess data is charged at 4c per megabyte, which is a reasonable rate in comparison to the major telcos, and there is also the option to pay $7 per GB to increase your data plan in any given month.