It's a simple question, but I can't find an answer anywhere and get confused.. Can I use Facebook Audience Network (FAN) in my apps on AppGallery of Huawei? If not, what ad networks can I use? and get earn from it.

Few Other Questions in my mind:

1)Should i have to use signed apk or test apk on AppGallery of Huawei?

2)Should i have to use admob or Amazon Mobile ads kit in Amazon App Store?