Smartphone battery habits and resale value rankings unveiled

Telia’s research highlights that the smartphone screen is the largest battery drain during travel, consuming 20‑30% of daily energy and even more at maximum brightness in sunlight. Automatic brightness adjustment and reduced screen luminosity can extend usage, while navigation apps also heavily tax the battery due to GPS, mobile data and an always‑on display. Experts advise downloading offline maps before trips to lower power and data demands.

A separate study ranked the most valuable used smartphones. The base iPhone 17 256 GB retained 99% of its price after ten months, followed by the iPhone 17 Pro at 98.7% and the iPhone 17 Pro Max at 98.73%. The iPhone 17e held 96.66%, while the Samsung Galaxy S26 was the only Android in the top five, keeping about 88.9% of its original price. The findings anticipate the upcoming release of the iPhone 18 line later this year.