2 Added specific chips to destroy, with link to iFixit
source | link

Under the assumption you do not trade state secrets I would:

  • Wipe the phone/do a factory reset (assuming the phone is still working)
  • Remove the SD Card (keep it for later use) (does not apply to the iPhone5, since it has none)
  • Open the phone
  • Locate the motherboard (the largest piece of printed circuit board)
  • Unseat or destroy the following chips as possible (See this iPhone5 Teardown Guide on iFixit for details):
    • Hynix H2JTDG2MBR 128 Gb (16 GB) NAND flash (on Step 15)
    • The A6 processor (on Step 16/18)
  • Dispose the parts at different times/different locations of an electronics recycling shop (Availability depends on country)

With this, an reassembly and successful extraction of data would be expensive and very unlikely.

Note: According to the iPhone Wiki, the A6 does not have a Secure Enclave, so nothing to do about that.

Under the assumption you do not trade state secrets I would:

  • Wipe the phone/do a factory reset (assuming the phone is still working)
  • Remove the SD Card (keep it for later use)
  • Open the phone
  • Locate the motherboard (the largest piece of printed circuit board)
  • Unseat the chips as possible
  • Dispose the parts at different times/different locations of an electronics recycling shop (Availability depends on country)

With this, an reassembly and successful extraction of data would be expensive and very unlikely.

Under the assumption you do not trade state secrets I would:

  • Wipe the phone/do a factory reset (assuming the phone is still working)
  • Remove the SD Card (keep it for later use) (does not apply to the iPhone5, since it has none)
  • Open the phone
  • Locate the motherboard (the largest piece of printed circuit board)
  • Unseat or destroy the following chips as possible (See this iPhone5 Teardown Guide on iFixit for details):
    • Hynix H2JTDG2MBR 128 Gb (16 GB) NAND flash (on Step 15)
    • The A6 processor (on Step 16/18)
  • Dispose the parts at different times/different locations of an electronics recycling shop (Availability depends on country)

With this, an reassembly and successful extraction of data would be expensive and very unlikely.

Note: According to the iPhone Wiki, the A6 does not have a Secure Enclave, so nothing to do about that.

1
source | link

Under the assumption you do not trade state secrets I would:

  • Wipe the phone/do a factory reset (assuming the phone is still working)
  • Remove the SD Card (keep it for later use)
  • Open the phone
  • Locate the motherboard (the largest piece of printed circuit board)
  • Unseat the chips as possible
  • Dispose the parts at different times/different locations of an electronics recycling shop (Availability depends on country)

With this, an reassembly and successful extraction of data would be expensive and very unlikely.