Does it harm my IPhone 4's battery if I charge it over night?

If I charge my IPhone over night and it gets to a 100%, will it harm the battery life if it stays on charge past its fully charged mark?

Nope no harm done

If you charge your iPhone's battery for a long time once it gets over 100%, yes, it could. Same for every other battery.

If it's just charging a little over, then it should be fine.

No it'll be fine I do it all the time

No harm at all. It can't overcharge

No, it will just stay plugged up, it will keep it at 100!

Any charging at all is never going to do much damage. If you overcharge the battery for hours upon hours, all you're doing is diminishing the life of the battery. Just keep an eye on it, if you're charging overnight you'll be fine because most of the time it'll need it by that time if you're not charging throughout the day.

Yes gradually all rechargeable batteries will 'wear out' but leaving an iPhone charging when 100% causes quicker degradation as you are unnesecarily charging it when it does not need it. I found out the hard way and now my iPod lasts around 2.5 hours

No, it doesn't harm your phone at all because iphones can't overcharge. Once the phone reaches 100%, it stops charging all together so the charger being in there doesn't make much of a difference. I normally charge mine overnight and take it off in the morning, no harm done!

No of course not. It's normal to leave it on charge all night.

No, it will automatically stop charging at 100%

Nope. I let mine die all the way down to 5% then plug it in and unplug it about 8 hours later when I wake up.

It will not overcharge. No Apple devices do as a matter of fact. Its fine, and actually usually recommended.