What you'll be notified about, and how to control it.
A wide range: motivation received, chat messages, challenge invites, someone giving your post an "awesome," bet-related updates, and more. Each type can be turned on or off individually rather than all-or-nothing.
Go to Profile > Notification Preferences, where every notification type has its own toggle. Turn off exactly the ones you don't want without losing the rest.
The most common cause is that notification permission got denied at some point — if so, you'll see an "Enable in Settings" button right inside the app's notifications screen that takes you straight to the right Android settings page.
Following a challenger or a public challenge means their activity shows up for you without needing an invite or a mutual connection — a lighter-weight way to keep an eye on people and challenges you're interested in.
Yes, your profile has a Followers list. Some follower details may be revealed gradually rather than all at once — check your own profile for the reveal option if you see placeholders.

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