How do you ask someone when they will call you in japanese?

Question

like are you gonna call me or when will you call me

Answer 1

The above translation was good, but to be a little more kind, you should say
いつ電話してくれますか？ (itsu denwa shite kuremasu ka?) <- this is more formal
いつ電話してくれる？ (itsu denwa shite kureru?) <- this is more casual.
You could change いつ (itsu) to いつまで (itsu made), and this will mean "By when will you call me?"

Answer 2

formally (to people in higher positions than you or strangers)
いつ電話しますか？
itsu denwa shimasu ka?

informally (to friends, younger people, family)
いつ電話する？
itsu denwa suru?