How to preserve electronic evidence?

Electronic Record Subpoena, Preservation, Authentication & Chain of Custody

Computer (including cell/mobile phone) text messages are sometimes used as evidence in legal proceedings. So what is the best way to save a text (or photo/video/audio) record as evidence? In other words, how can an investigator secure digital evidence today so he can prove its chain of custodylater in a court?

Suppose your estranged spouse (husband/wife) cell phones you a photograph or text message relevant to a future divorce hearing. Or suppose a business partner (or manager, boss, politician, government official) sends you a video important to a dispute/lawsuit -- s*xual harassment, employment discrimination, breach of contract.

https://www.lawweb.in/2012/09/how-to-preserve-electronic-evidence.html