No, you cannot use your personal cell phone or other electronic devices during the Military Entrance Processing Station (MEPS) processing day. These items are strictly prohibited in testing and examination areas to maintain security, integrity, and focus.

MEPS Phone Policy Explained:

Secure Storage: Upon arrival, you will be required to store your phone and any other personal electronics in a designated locker or secure area for the duration of your processing.
Zero-Tolerance Enforcement: Using a phone during testing (like the ASVAB) would be considered cheating. Using it to take pictures or record inside the facility is a serious security violation. Either action can result in immediate disqualification.
Limited Access: You may be allowed to briefly retrieve your phone during scheduled breaks or lunch, but its use is typically restricted to that time and place. Do not expect to use it freely throughout the day.
Preparation: Inform family/friends that you will be largely unreachable. Bring a book or magazine if you want something to do during waiting periods.

For context on other personal aspects of military life, you can read about Can I have a girlfriend while in the military?

For an external, official resource on MEPS preparation and conduct, you can review the guide from Today’s Military.