Game maker Sega is rolling out five free apps on the iOS and Android platforms, with plans to launch new titles every two weeks.

Some 15 classic games already offered on the App Store will be moved under a new Sega Forever brand. In a statement, the company explained the moniker is “a re-awakening of archetypal gaming” and signalled the “beginning of a retro revolution that will transport players back through two decades of console gaming.”

The first five games are Sonic The Hedgehog, Comix Zone, Phantasy Star II, Kid Chameleon and Altered Beast.

“As the Sega Forever collection expands through months and years, it will include both official emulations and ported games that span all SEGA console eras, each adapted specifically for mobile devices while remaining faithful to the original games,” the company said.

All games run advertising, are playable offline, and include features including cloud saves, controller support, and leaderboards.

Mike Evans, CMO of Sega’s mobile division, said Sega Forever is: “about allowing fans to reconnect with past experiences and share them with family and friends in an accessible and convenient way.”

“The games were never designed for ads or in-app purchases, which is why we’ve maintained this faithful emulation experience,” he told GamesIndustry.biz, adding: “there’s enough revenue to be made from the advertising side that we don’t need very high volumes of conversion from the in-app purchases.”

Users will also have the option to buy the games for $1.99 and remove ads.

Some users have been critical of the games.

Digital Foundry’s John Linneman told Nintendo Life: “There are loads of dropped frames, hitches and skips…the issue here is that it skips and stutters during gameplay. And when a notification occurs, it gets much worse. So it never plays smoothly.”

Meanwhile rival Nintendo’s latest app, Fire Emblem Heroes, earned more than $2.9 million in worldwide gross revenue and was downloaded more than two million times within a day of its launch in 39 countries.