Overnight, my iPhone has been dropping about 30% of battery. As well, battery also seems to be getting chewed up much faster during the day, when I use my iPhone, compared to normal. For example, I'd lose 1-2% of battery for every second of normal usage, for example, using WhatsApp or internet surfing. This is about double the amount I used to lose. When I play iTunes songs for about 1 hour, I'd lose about 25% of battery these days. I used to lose only 10% when I did this. This has been the case for the past two days. Previously, it used to drop only about 5% every night. However, I don't remember installing any new apps, themes or tweaks recently, so what could the reason for this sudden battery drain be? Any suggestions? I also haven't changed or adjusted my iPhone's settings since then i.e. screen brightness, etc. I have an iPhone 4 (5.0.1), jailbroken.