Outside Market

Hello everybody!

I am really not sure about something.

Is it against google play terms to promote an app outside the market ?

like for example in one app available in android store when a user open it it ask him to download another app which is not live.
so he will be downloading an apk and installing it without google play.

is this against google play terms ?
I just don’t wanna get banned again some stupid reason.

Please any suggestions.
Thank you