A diet based on 1200 calories daily is the recommended minimum for safe and healthy weight loss. This is because 1200 calories will generally provide an adequate nutritional intake for most individuals, yet still allows the reduction of calories to the level that most dieters require in order to lose weight.
Stand-by time (battery life) Stand-by time is the officially quoted longest time that a single battery charge will last when the phone is constantly connected to the GSM network but is not in active use. The stand-by time is highly dependent on the cellular network environment, such as the distance to the closest GSM cell tower (base station).
The real killers of lithium batteries(the kind in your phone), is heat & frequent full discharge/recharge cycles. They have a design life of 3 ~ 5 years, & will last much longer if not subjected to frequent discharge cycles below 40% of capacity. Apple recommends you let your battery fully discharge/recharge once a month...every couple of months will be just fine. So, to maximize your battery life, charge your phone as often as possible & avoid high heat.