He told Gambling Insider: "Since atmosphere and ambiance are difficult to replicate through an online device, how can online slots match the land-based experience?

"What online slots do offer is freedom at your fingertips to play a large variety of titles whenever and wherever you want. What’s missing are the bells and whistles."

Ciavarella says slots in casinos must generate enough cash flow to justify the expensive floor space they take up. This can both hinder and support their development."

He added: "So, deciding which bells and whistles are more important remains interesting – it is personal taste after all.

"The possibilities lie in the same features that make online slots so convenient and flexible. For instance, how about using mobile and online devices as an entertainment channel to continue to engage players through prize creativity, linked to loyalty and cross-over promotions?"

Ciavarella was speaking to Gambling Insider magazine for the Big Question section of the July/August edition.

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