The free medium coffee order is the latest announcement from McCafe's 30th-anniversary celebrations in Australia.
"Tomorrow, coffee is on us! We are shouting free coffee to customers across Australia to thank them for their loyalty and support over the past 30 years," Group Brand Manager Lancy Huynh said.
Free coffee is the only way to celebrate 30 years of serving great quality coffee to a nation of coffee lovers.
"We are hoping our customers enjoy their morning coffee or afternoon pick me up on us."
According to the fast food giant, McCafe barristers serve up more than 230 million cups of coffee (and other hot drinks) per year, accounting for an impressive one in four coffees sold in Australia.
In addition to the free coffee on offer via the app, the McCafe coffee van is touring Australia.
It will be at Mrs Macquarie's Chair in Sydney from 5:30 am - 2 pm on Tuesday, May 30, before moving to City Botanic Gardens in Brisbane from 5 am to 1 pm on Sunday, June 4, and finally Strand Park in Townsville from 5:30 am to 2 pm on Tuesday, June 6.