Zara and Mike Tindall have proven to be popular during their current trip to Australia, and it seems the couple's likeability is only increasing.

Zara, 42, and ex-rugby ace Mike, 45, have been married since 2011 and have established themselves as one of the Royal Family's best couples, as they are "honest, funny and candid", claims Royal commentator Robert Jobson.

Mike has been a firm favourite with the public for many years thanks to his rugby career and other media work, such as his hit podcast, The Good, The Bad & The Rugby, and his stint on ITV's I'm A Celebrity...Get Me Out Of Here!

Meanwhile Zara - a British equestrian and Olympian - is naturally "hard-working and authentic", meaning people "warm to her" wherever she goes, much like her mother Princess Anne, Robert claims.

Mike and Zara Tindall
Zara and Mike Tindall

"Zara has always been open, which is why people seem to see her as relatable pretty much everywhere she goes. She’s got the likeability X-factor," Robert wrote in the Daily Mail.

He went on to claim that Zara and Mike, who are parents to Mia, nine, Lena, five, and two year old Lucas, are also likeable as they are often seen beaming for the cameras and are "unafraid to show affection".

Combine all of this together, and it's easy to understand why the Tindalls have earned millions as a couple. It's now thought that Zara and Mike could be more popular than Prince Harry, 39, and Meghan Markle, 42, with the pair now being frontrunners for any commercial deals instead of the Sussexes.

Zara Tindall and Mike Tindall
The Tindalls are 'unafraid to show affection'
Meghan Markle and Prince Harry
An expert claims the Tindalls are now favoured over Harry and Meghan

"It’s been suggested that the Tindall’s earning power could have even greater potential than that of Zara’s cousin Harry and wife Meghan in Montecito," Robert said.

Zara and Mike have been enjoying their annual holiday to Australia over recent weeks. The duo jet off to Oz every January to attend the annual Magic Millions events, of which Zara is an ambassador for.

Zara and Mike Tindall
Zara and Mike have been married since 2011

Photos of the Tindalls Down Under showed them packing on the PDA at Byron Bay, with Zara even cheekily pinching her husband's bottom after a swim in the ocean.

Australia is understandably a special place for Zara and Mike, who famously met in Sydney in 2003 during the Rugby World Cup. The pair holiday in Oz every year and have always spoken fondly of the time they've spent Down Under.