I haven't had used this app still yet, but app occupies too much space (storage)for what I don't know about,even I don't sign in with this app for any thing else, might be I've had signed in my MS Office and One Drive;but while I try to authenticate to sign in via any Microsoft apps installed on my phone,app doesn't respond is the primary reply,and then sign in or create account is followed,eventhough I try again and again either to sign in or to create account .....app isn't flexible enough..