Unfortunately, the battery life of smart phones, relative to feature phones or plain old mobile phones, is very poor. Whereas my “feature phone” had a battery that typically lasted up to two weeks, most smart phone users re-charge their phone every day, and some times several times per day!
User research on smart phones finds most people use their phone for 4 to 10 hours before they need to recharge the battery. While many users recharge the battery overnight, every night, there are many users that recharge throughout the day, at every chance they get, such as plugging in when working at their desk.
There is not a single magic bullet to fix the problem of smart phone battery life. Batteries improve each year, but only by the low single digit percentages, while power demands rise much faster in new devices. The physical size of a smart phone or tablet also limits how large a battery can be used, putting a constraint on solving the problem by just adding a bigger battery.
It would be helpful if there were a single “Battery Saver” option that would enable a configured set of features for maximum battery life. But on most phones, no such feature exists. Instead, you need to consider disabling unused features manually. But most smart phone users are not going to know which features to select (and personally, I think this needs to be mostly automatic) to achieve best battery life.
- If your phone or software allows, disable software features that do background checks throughout the day, even while you are not actively using the phone. That is, avoid having Facebook or Twitter update constantly, or continually checking for email. Surprisingly, some studies have found that about half of the battery power is consumed during the nearly 90% of the time the phone is supposedly idle or sleeping!
- Choose a display theme (if available) featuring a dark background. Lighting up the LCD for, say, a black text on white background, uses much more power than white text on a black or dark background.
- If Wi-Fi is regularly available, say at home or your office, then use Wi-Fi instead of the cellular data link. Not only will your mobile service provider like you, but Wi-Fi reduces the power consumed for data transmission. Even though Wi-Fi uses a considerable amount of power, data transmission is typically 10 to 20 times faster than over a typical 3G link. That means the Wi-Fi transmitter is turned on for a fraction of the time compared to the 3G transmitter.
- If you know you will not be using Wi-Fi, then disable it. For example, while driving or walking, leave Wi-Fi disabled to avoid constantly searching for available Wi-Fi hotspots.
- Location services can also use a lot of power quickly. GPS, in particular, uses a considerable amount of power. Many smart phones use a variety of methods to determine your location including knowing where a currently used Wi-Fi access point is located, or using the known location of a cellular servicer tower site, or GPS. But if you are not using location services, disabling this feature will cut power needs. However, avoid turning it off and back on frequently as it can take 30 seconds (or so) for GPS to re-acquire location data rather than just referring to a last known, good location reference.
- Turn off Bluetooth if you are not using Bluetooth.
- Use audio alerts instead of vibrate alerts.
There is a lot of research being done on ways to improve battery life. This work includes the development of new battery technologies, but also improvements to the radio network and communication protocols, smarter operating system features that attempt to predict when software or hardware can be set for reduced power modes, or which limit big data downloads (such as app updates) to when plugged in on charge or connected to a Wi-Fi network. There are also tricks that app developers can incorporate to reduce their app’s power needs. But for now, these are all for the future.