Write Blockers: Write blockers are not effective for mobile phones because forensic acquisition requires two-way communication and deploying agents (like ADB for Android) on the device
Hashing:
PC forensics: Hash taken before and after creating forensic image - both must match
Mobile forensics: Hashes won't match before and after acquisition due to background services continuously running (alarms, apps) and agent deployment
For mobile phones, meaningful hash is taken only of the forensic image itself
Physical Bit-by-Bit Imaging: Not possible on modern mobile phones (Android 7+ or iOS 10+) due to file-based encryption
Encryption keys stored in Secure Enclave or Trusted Execution Environment
Even physical copies would only contain encrypted data