Are there any iphone apps that charge your battery?

I've heard of battery boost magic and i was gonna buy it but does it really work? Like does it charge your phone even when you don't have a charger?

May be the below link may help you out

The only thing that can charge your battery is electricity from the charging cable. The battery apps you've heard of don't charge your battery, instead they try to make the phone and other apps use it less. I've used apps like this on Android phones and they do work (the battery lasts 10-20% longer), but I haven't tried any apps like this on iPhone. My guess is they wouldn't work very well on iPhone because apps aren't allowed to make many system changes.