I get a little obsessive about clearing iOS Badge App Icons and find them to be distracting, so I prefer to disable them.
How to disable a Badge App Icon for any iOS app:
Settings > Notifications > [App Name] > Badge App Icon > Disable
That’s great but what about when your Twitter Badge App Icon setting is missing? Bring back the setting by turning off Badging in the Twitter app:
Twitter > Me (Profile) > Settings (Gear Icon) > General > Badge App Icon > Turn Off
June 06, 2015