It have the Demon Summoning Program (self-explanatory) and have skills equipping options. Set skills (if he have the stat requirement) and use them with HP/MP in battle. It also can scan the enemy for their stats, elemental resistances and skills (dunno how it'd read the Final Boss. I know some boss battles can list HP/MP as ???/???)

It also comes with the Harmonizer, which basically lessens the enemy's attack and strengthens his own in an attempt to make things more equal (things still hurt if they're strong or he's too low leveled...) for everyone within its range, as an IC explanation why he can punch out demons or survive. Or how normal civilians in escort missions can survive their first demon attacks.

So yeah, in canon he relies on it to survive in battle.