I liked Mailbox but for some reason, I think it drains my battery, much more than the Gmail app from Google.. I know it does not make sense that it's at backgr

I liked Mailbox but for some reason, I think it drains my battery, much more than the Gmail app from Google.. I know it does not make sense that it's at background, not working and using the same push notification service as Gmail app. Is there any logical explanation? Or is it just psychological?