Their was another post about this charging issue and I explained it all basic on my educational level with electronics. Their were some people who turned it into and utter and complete joke. 99% had no electronic background but made tons of dumb comments. As the post went on a couple people that were using the iPad charger on their iPhone ruined their iphone battery. Once these people started posting that these people stopped with their stupid replies. the reason volts, watts, and amps are put on chargers are for a reason or else why would they put them on.





I can get really technical with formulas on this but I will go with a very simple one. All Apple chargers are 5 volts. Amps is the amount of current flowing into your device to charge your battery. Watts are easily calculated V x A = W





Example. Charger is 5 volts and is 1 Amp so it has 5 watts (iPhone charger)

Charger is 5 volts and is 2.1 Amp so it is 10 watts (iPad charger)





That one I just rounded up the number like apple did.





Most PC's 5 volts and it is .5 amps so it is 2.5 watts





Slow. Charging your battery is best to get the most out of it but who would want to plug their new iPad into their PC and wait 24 hours for it to charge??? No one, not even me. Despite it saying "not charging" on the screen plug it in your PC overnight and remember what you started off with, turn off the screen, let it go for 4 hours, and YES it will charge at a VERY slow rate. The screen says not charging, but give it a try and you will see that it did charge up but very little.





Has anyone looked up the battery capacity of the new iPad verses the older generations??





iPad 3 11,500 mAh battery 42.5 watts

Pad 2 6,944 mAh battery 25 watts





So with their 5 volt charger 2.1 Amp 10 Watts you are fine because you are not going over the battery specs .Pretty amazing how they achieved that many mAh just by making it slightly thicker. Very technical how it was done but not for this discussion but it is almost double capacity.





Now let's talk iPhone.





IPhone 4S 1,420 mAh battery (1.42 Amps)





5 Volts x 1.42 Amps = 7.1 watts





iPad charger is 5 Volts 2.1 Amps 10 watts. Now you see the problem? Will it work Yes, but you are over charging (forcing to much current) your battery. End result you are decreasing the life of your battery.





Apple says you can use any charger and you can see above a simple formula in simple math. So why would you use a charger that is 2.1 Amps 10 Watts on a battery that is 1.42 Amps = 7.1 watts





Does anyone know what the cost is for Apple to put a new battery in your phone? I am curious on that one and would guess its not cheap.





Their is a formula in simple math. Can you use the ipad charger on your iPhone ? Yes. Will it shorten your battery life using the iPad charger on your iPhone? Yes.





This is the simplest formula broken down into simple math.