This brand name is a playful take on the word "retina".
Retiny has only six characters and three syllables. Successful brands using three syllable names include Delicious, Toshiba and Adidas.
Retiny.com is a dot-com domain. Dot com domains are the most sought after domain extension in the world, famously used by websites like facebook.com. When most people think of a website, they think of a dot-com.
This domain was first registered in October 2016. Older domains have an advantage when ranking in search engines.