Assuming that you're talking about Homebrew App Store for Wii U, it should go in
wiiu/apps. Otherwise, it should go in apps.
In short:
-
Wii U homebrew apps go to
wiiu/apps
-
Wii / vWii homebrew apps go to
apps
If you're installing their forwarders, they should go to
install folder on the root of your SD card. If you don't have one, create it now.
If you put
Nintendont in
apps, it won't appear in either
Wii U's Homebrew Launcher nor
WUP Installer, but instead in
vWii's Homebrew Channel (i.e. on vWii side).