I would like to know if there's a sequel to The World Ends With You?

I'm planning to buy and play the game The World Ends With You. I want to know if there's going to be a sequel. I have been doing my research and so far there have been rumors, but it has been unconfirmed. I also know that an app has been released to the iPhone app store. It is called The World Ends With You- Solo Remix. What is that? Is that a sequel to the DS game or is it actually the same game that has been made available on the app store? I would sincerely like to know! If you have any knowledge regarding these details be sure to let me know. Also is this game worth playing. I've played Kingdom Hearts 3D's: Dream Drop Distance and these characters show up from The World Ends With You. That is how I found out about this game. I think that they would be really cool if they showed up in the final game of Kingdom Hearts that is coming out next year. Will Neku and the others be in that game too? I have a lot of questions, but so far I haven't been getting any answers at all. If you anything about any of these things, once again let me know.

I know I typed a lot… But please take the time to read what I have got to say. I'm dying to know if a sequel comes out to this game next year or not or if they are going to show up in the final game of Kingdom Hearts more or not. Be sure not to skimp out on any of the details!

They probably won't have a sequel soon even if they are making it because the current Square Enix staff are busy making Final Fantasy XII and Kingdom Hearts 3. Also there are 2 apps, Solo Remix and Live Remix. I only have the Live one, but it's not a sequel. It is a game where you collect badges and fight noises and other teams. If I remember correctly, the Solo Remix cost money while Live was free. I'm sorry but I don't really know the differences between them, though I do recommend playing Live 'cause it's free and quite fun for fans.
Kingdom Hearts 3 probably wouldn't feature them, because they were in a world in Sora and Riku's dreams. There's still a chance they might appear briefly as a playable world though.
Hope I could help.