Processor performance can be tested using benchmarking apps such as Geekbench, AnTuTu, or Androbench. These apps perform a variety of tests and provide a score that can be compared to other devices.

Battery life:

 While running performance tests, use a battery benchmarking app like PCMark or GFXBench to measure a phone's battery life. You can also manually test the battery life by performing regular activities on the phone and noting how long it takes for the charger to drain.

Display quality: 

To check for picture quality, brightness, and other display quality metrics, use a display testing tool like DisplayMate or CalMAN. By checking the screen's colour reproduction, viewing perspectives, and brightness in various lighting situations, you can also manually test the display's quality.

Camera performance:

 To assess the image quality of the camera, including colour correctness, sharpness, and noise, use testing programmes like DxOMark or Camera MX. Additionally, you may record videos and snap photos in various lighting situations, then compare the results on other gadgets. Study the Phones specs to ensure a seamless phone selection and knowledgeable access.