Recovery of data from mobile phones is a rapidly changing technology area. When we speak about phones, we deal with the internal memory of a phone, rather than portable memory that can be installed in the handset (such as a micro SD card).
Mobile phone failures fall broadly into one of two categories:
Basic electronic failure
- Power/button issue which makes it impossible to power the phone on
- Display/screen issue which makes it impossible to inputs data (e.g. PIN entry, App selection)
- Connector/battery issue which makes charging impossible
These are the easier failures to work with. In these cases, getting data from the phone is achieved by effecting a temporary repair which makes the phone addressable so that the data can be exported.
Internal electronic/functional failure
This is a failure where the phone cannot be repaired temporarily, e.g. a failed CPU
For such failures, it is necessary to connect directly to the phone’s internal memory microchip(s), and there are usually two possibilities.
JTAG: Tapping into the phone’s circuit board at prescribed locations in order to gain direct memory access
Chip-Off: De-soldering the memory components from the phone and interfacing directly to the contacts on these microchips using specialist adapters.
Once access to the memory chip(s) is established, a logical image of the memory can be made, from which the data can be extracted.