If you want to keep your privacy jumping across the border, you have two options: 1. Fly into Tijuana or Juarez and walk across the border with anything you want (phones, guns, drugs, prostitutes, lizard people, etc) 2. Buy a burner and trash or wipe it before crossing back Encryption of phones is suspect as hell. You pretty much need to trust google. If you trust google, you already don't value your privacy.