Installing an iOS or Android update can sometimes have an unexpected short-term effect on a phone’s performance. Animations may become sluggish, the device may feel warmer than usual and battery consumption can increase. These symptoms are generally temporary, although older hardware may remain slower when running a major new software version.
One reason is that the phone performs extensive background work after the installation. On iPhones, Spotlight reindexes stored data, while Android devices also reindex information to ensure that everything is properly organized after the update. This process can take hours or, in some cases, days.
Reindexing increases CPU and GPU activity, leaving fewer resources available for apps and system animations. Once the process is complete, performance should normally return to its previous level. Keeping the phone connected to a charger and Wi-Fi can help the work finish sooner. Apple says some indexing tasks on iPhones only complete while the device is plugged in and not being used, while Sony says Android indexing generally takes no more than two days.
Older phones may be affected more noticeably because their chips have fewer performance and efficiency reserves. Major updates are also commonly designed with newer hardware in mind, and older devices may struggle with additional features, apps and more complex animations. In those cases, the slowdown may persist rather than disappearing when indexing ends.
If the phone remains slow, restarting it may help. Users should also update their apps, since older versions may not be optimized for the latest operating system. Freeing storage space can improve performance as well, because insufficient free space can interfere with basic system tasks.
Checking battery health is another option. Some smartphones reduce processor speed when the battery is in poor condition to help prevent unexpected shutdowns. Replacing the battery may improve performance in that situation. A factory reset is a more drastic measure, while downgrading the software is more complicated and is not supported by every phone.
If the device continues to perform poorly after these steps, its hardware may simply be struggling with the updated software. Contacting the manufacturer can help determine whether the issue is known, although persistent problems may indicate that the phone is nearing the end of its usable life.
Sources: Engadget.