Is Weverse required for every act?

No. JYP and several independent labels use other membership sites. Read the act’s notice.

Are Bubble messages the same as Weverse membership?

No. Bubble is a paid messaging product; Weverse membership is a fan-club tier that can unlock concert codes.

Билеты · 공식 K-pop 팬 앱 디렉터리 (위버스·버블·Lysn 등)

Official K-pop fan apps directory (Weverse, Bubble, Lysn & more)

Membership cards and presale codes live inside the app named in the notice — not in random Discord forwards.
Push notifications matter on on-sale mornings; enable them for the artist’s channel only.