Comprehensive Mobile Refurbishment -- 2

I need a professional with a broad knowledge base on all types of mobile phones for a reflash job. My goal is to upgrade all my devices to a newer operating system, providing a fresh start and better user experience. Key tasks will include: - Complete data wipe: Prior to the flashing process, all data and settings will need to be totally erased from my devices. - OS update: The upgraded operating system should then be installed. Applicants should have a solid background in mobile refurbishment and a deep understanding of various mobile phone brands. Expertise in data backup and data security will also be considered an asset. It's crucial that you can provide guidance on maintaining the functionality and security of the devices post-update.