It's for sure an android system.
I decompiled the NavApp.apk and found the android manifest.
One of the classes I found:
.class public Lcom/tomtom/apparch/setting/SafetyLock;
.super Lcom/tomtom/apparch/setting/Setting;
.source "SafetyLock.java"
I'm digging deeper as we speak (my intent is to get rid of the darn speed lock)