You cannot do this.
Apps running in the background can only do the following things: continue on something that won't last too long, play music or store current state in background.
Would you like it if one of your apps that you had been using picked up a phonenumber that called you and posted it on the internet? That may be one of the reasons why apple doesn't allow this…
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…