Yes, Pokemon can make a comeback on the iOS platform. Since the app will use the phone's cameras, speakers and sensors, it will give players a sense that they are playing within the game itself. When it is released in Japan and the U.S. especially, it should be very popular with younger cell phone users.
Pokemon remains, and has always been, immensely popular over several demographics. The release of Pokemon Go especially shows that their is still an appetite for new installments of these games and the franchise is more than capable of making a huge comeback on the iOS platform - the real argument would be if the series ever went away and was in need of a comeback.
Many people today are embracing and enjoying seeing things from their past. Pokemon was very popular back in it's day and bringing it back could bring a huge success. I think Pokemon would be successful on any platform, not just iOS. But, because many of the "techie" people are the ones who enjoyed Pokemon and are the ones who have Apple products, I think it would be even more successful on iOS.
Unfortunately, for those of us born at the right age to remember the glory of Pokemon season 1, the beloved world of Pokemon is faded and gone. While I completely understand the desire to continue to make money for your business, the business of Pokemon needs to go to the wayside. There are Pokemon now in the shape of garbage cans and ice cream cones. Gone are the days when the little monsters were creative. Now they are just adding eyes and mouths to random household items. Let it go, Pokemon. Let it go.