R.L. Mathewson, a self-published author who uses the digital publishing platform Smashwords, has made the top selling list in the iBookstore. Mathewson’s romance novel Checkmate hit No. 1 in Apple’s US, Australia, U.K. and Canada stores only a couple of days after being published.

But Mathewson is not the only author using Smashwords who has made the top sellers list in the iBookstore. Kirsty Moseley‘s Always You hit No.7 in Australia, and No. 20 in the U.S. and the U.K. Jillian Holmes‘ Temporary Kiss reached No. 7 in the U.K. iBookstore. Isabelle Rae‘s When Summer Ends reached No. 8 in the U.K. S.H. Kolee‘s Love Left Behind hit No. 5 in Australia and No. 10 in Canada. Marie Kelly‘s Billionaire’s Revenge reached No. 2 in Australia and No. 8 in Canada.

Smashwords’ founder Mark Coker blogged the news, explaining the Apple is the biggest retailer for Smashwords’ titles: “My advice to authors:  don’t underestimate Apple.  If you’re not there, you’re missing out.  Every new country they launch represents a new micro-market, an opportunity for you to become a big fish in a small but growing pond. The authors who get out there first and establish footholds today will become the bestsellers of tomorrow.”