does this actually have any relation to reddit, or is that just a comparison? Your description doesn't really make it clear, it seems like it might not be but you really mention reddit a lot.
if it isn't linked to reddit, then i don't really understand your tagline. what is a "private reddit"?
Trigger uses Reddit-like structure but in for your private discussions. So it provide more organisation to your conversations, or currently messaging apps.
Things are easier to find, you can have much better flow with all the conversations.
The comparison to reddit is terrible and confusing. I would remove this ASAP, because all this really is is a What'sapp group conversation, with the twist that you can group things by topic.
if it isn't linked to reddit, then i don't really understand your tagline. what is a "private reddit"?