Below are some sketches of how I envisioned the technology described in the science fiction novel Old Man’s War by John Scalzi.
PDa
The PDA is a Personal Device Assistant that helps recruiters get by their day-to-day, like a smartphone. Recruiters are able to check times, get directions, set alarms, make appointments, check menus, etc.
BrainPal
The BrainPal is like a PDA but it’s encrypted in the brain and it communicates to you through speech. Recruiters communicate back to it with speech as well, like Siri on the iPhone that we have today.
Creche
In the novel, recruiters are placed in a creche to have their consciousness transmitted over from their old body to their new body. Their new body is stronger, faster, healthier, and with heightened senses.