My iPhone charge is getting low fast?

I have the IPhone 4S, the original charger broke so now I have to use an off brand charger. Sense I have used it my iPhone dies very very quickly. Is it just me and I use it to much or the off brand charger not as good compared to apple's charger.

The iPhone battery generally dies quite quickly if you use it a lot. However, maybe the off brand charger you are using is not very good. You should probably buy an Apple charger.