Ah, I found the downside to using Twitter website instead of app on mobile: notifications don't allow just mentions. 
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Replying to @o_guest
How do I do that in the app? Can't find it in settings (android)
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Replying to @DrGBuckingham
On android myself, see below.pic.twitter.com/NpwaJBVrqj
1 reply 0 retweets 0 likes -
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