Sega Forever will see a change that will focus on ported titles, not just emulated ones. Sega made the announcement today on March 1st, saying in a straightforward manner that the ported titles they've released (technically, updated free re-releases of previously-released games) have been more played than the emulated titles. As such Sega says their "plan this year is to focus on porting titles natively. As a result of these changes, the cadence of releases will reduce."

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Sega does seem to be teasing what's next with an image, file name "Could-this-be-a-teaser-question-mark.png". The silhouetted art appears to show Dynamite Headdy characters and...are those the monkeys from Super Monkey Ball" Considering how big those games were in the early days of the App Store, and that they don't work now, they'd make a lot of sense to return to Sega Forever.
The ported titles having more downloads makes sense in several ways. One is that they included the Christian Whitehead and co. Sonic ports. It would be tough for any Sega ported title to match that degree of quality because Whitehead, Stealth, and crew were decades-long Sonic obsessives who not only brought intense passion but a deep knowledge of how those titles worked, which made for ports with exceptional quality. Virtua Tennis Challenge [Free] was at least an actual mobile game, updated for 64-bit and modern devices. Crazy Taxi [Free] is Crazy Taxi.
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