Smartphone users routinely find themselves left hanging when, after a few phone calls, a little internet surfing and a quick video on the way to work, they finally find themselves with a depleted battery and half the day left to go.
"Modern smartphones, with their big displays and fast processors, use significantly more energy than classic basic mobiles," says Michael Wolf of Stiftung Warentest, a German consumer products tester.
Thus, it's best to learn some tips to save energy and keep your mobile working for the full day.
Display lighting is the biggest battery drain.
"It's best to pick the lowest possible lighting setting for the display and to set the shortest possible interval before standby mode kicks in," advises Bjoern Brodersen of Areamobile.de.
Also consider letting your smartphone regulate its brightness based on surrounding lighting. But that's only one possible offender. Wi-fi, Bluetooth, satellite navigation and ever-active apps also take their share of battery power. Always consider turning off unused apps, especially those that eat up power, recommends Bettina Seute of Teltarif.de.
If you're in a bad reception area, consider switching from UMTS or LTE modes to straight GSM. Otherwise, the device will continuously search for a signal, eating up power.
Apps are also known to use up energy.
"Free, ad-financed apps are a bigger hit on the battery than necessary, since they're always broadcasting the location of the smartphone or tablet to call up location-based ads," says Brodersen.
But always take operating system updates as soon as they're available.
"Updates don't just close security gaps: they can improve the energy efficiency of a smartphone."
Seute also advises keeping an eye on widgets that might be using up power when they're not needed. Also consider turning off push functions for emails and contacts. Always active, they're a drain.
If that's not enough, consider some special energy-saving apps, though care must be taken that they won't disrupt the system.
Otherwise, consider setting controls to limit the power consumed by functions like the display or wi-fi. And, at night when you're sleeping, don't forget the option of just turning off the device or putting it into airplane mode to save on power.
Don't forget external factors. Cold will hamper a mobile, so always carry them in inside pockets if you visit a chilly country. And, if the phone allows battery swaps, carry a charged-up backup battery.