Todayonly, Apple is hosting a special Apple Watch Activity Challenge which rewards users who complete a workout for 30 minutes or more with a trio of animated stickers and a virtual trophy in the Fitness app, however, the virtual reward doesn’t appear to be showing for some users, despite them completing the challenge. Taking to Twitter Applehas announced its next Activity Challenge for Apple Watch users. This time, Apple is celebrating International Women’s Day with a challenge that will take place on March 8. Apple says: On Hhmg.