A phone that feels slow does not always need to be replaced. Often the cause is something that can be fixed with simple steps.
Common causes: full storage and background apps
When storage is almost full, the system becomes harder to work. Likewise, apps running in the background can burden the device. Start by deleting files and apps that are no longer needed, and closing apps that are not being used.
Restart and update regularly
Restarting the device can clear temporary processes that have built up. Also make sure the system and apps are updated, because updates often fix performance and security issues.
When replacing it is worth considering
If the phone has been cleaned, updated, and restarted but remains very slow for your main needs, or its battery has declined a great deal, replacing the device can be a sensible choice. Before that, back up your important data so it is not lost.
Note: This article is a general review guide and usage analysis, not the result of hands-on testing of a specific unit.