PORT CHARLOTTE — The Rays are, finally, starting single-game ticket sales on Friday, and have another change-up for fans: All ticketing will be done through the MLB Ballpark app on a mobile device, meaning no paper or printed out tickets.Sales start at 10 a.m. Friday on raysbaseball.com and in the app, and then will be available starting 10 a.m. Monday at all outlets, including the team store at Tropicana Field and by calling 1-888-FAN-RAYS. There will be the usual pre-sales for season-ticket holders, corporate sponsors and Rays Insiders (at 10 a.m. Thursday, with free registration available at raysbaseball.com/newsletter by noon Wednesday).The Rays used a similar mobile only ticket policy for the playoff games last season. Team officials in the press release Tuesday cited "a continued focus on innovation and technology,'' in making the MLB Ballpark app “the center of the fan experience.” The Rays also converted the Trop to be a cash-free facility last season.“Over the past decade, the tremendous growth of mobile technology and content has revolutionized the sports and entertainment industry,” team president Brian Auld said in the release. “Our fans have come to expect the same convenient and interactive mobile experience that they get through other first-class national brands. Making the mobile platform a central piece of the fan experience is critical to driving fan satisfaction.”The Rays have discontinued some of their nightly specials, such as the $7.11 Friday tickets, but have been exploring and are expected to implement some type of monthly pass plan.They will continue to offer free tickers to select home games to military, teachers and first responders through the Salute to Service program, $2 kids tickets for members of the Rays Rookies club, and $15 seniors tickets for select weekday day games.