This guide for iPhone and Android is a good start. Not all their recommendations are obvious. https://www.cisa.gov/sites/default/files/2024-12/guidance-mobile-

This guide for iPhone and Android is a good start. Not all their recommendations are obvious. https://www.cisa.gov/sites/default/files/2024-12/guidance-mobile-communications-best-practices.pdf https://www.cisa.gov/sites/default/files/2024-12/guidance-mo... For a deeper guide, check out the CISecurity benchmarks for your smartphone. They go a bit deeper. But the CISA guide will get you most of the way there. https://www.cisecurity.org/cis-benchmarks https://www.cisecurity.org/cis-benchmarks