I know there are forums all over the internet but why not have a forum here for people having issues with an app or any other related issue since the developers would be able to reply where they post the apps?

Well, I don't think ROMers upload their ROMs to third party app stores, so there is little reason for them to come here and expect to find a bunch of feedback/complaints about their ROM not working with certain apps. The best bet is to give that feedback in a forum that the developers watch.

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