My first recommendation is not Here Drive. It remains the worst navigation app I have ever used in the western United States. Only Apple's app outdoes it for stupid in the places I go.
Directions in Arizona, New Mexico, and west Texas range from basic/acceptable (some of the time) to inefficient to perplexing (being polite). The following are just a few examples to hopefully demonstrate my comments are not meant as hyperbole. First, it never figured out that several major east west roads in the East Valley in the Phoenix metro area cross highways more than once so even with routing set correctly it would give directions off a freeway 10+ miles from the correct exit. As a second example, it insisted the fastest route from Phoenix to Albuquerque is via Flagstaff (due north and then east) instead of the direct northeast diagonal along SR87 and 260. The route via Flagstaff is 90 minutes to two hours longer. Out of curiosity I left it on to see how long it would continue to tell me to make a U-turn back to Scottsdale and then go to Flagstaff - it kept directing me back for most of the drive to the SR87/260 intersection in Payson (about 90 minutes). Then there was the amusing instance when I was looking for the nearest Trader Joes in Tempe and the directions were a mile + loop back to the same intersection where I was parked (it was on the other side of the road). Its real time traffic is also quite bad and the maps are disgracefully out of date, in spite of the fact that updates to the map sets happen pretty regularly. It does not know, for instance, that there is a direct route to the FedEx depot east of the El Paso Airport and gives directions when coming from the west to loop completely around the airport. The direct road has been open for some time. Finally, it still thinks you can make a right turn off one of the I-10 exits in El Paso (Cotton to be specific) in spite of the fact the things right of the ramp are the 100+ year old Southern Pacific Railroad, Rio Grande, and Mexican border. I honestly keep it on my phone for occasional amusement and to see if they have bothered to update their algorithms to something other than schizophrenic.
With all of that said, Copilot is very good all around but has slightly choppy voice prompts. The other downside is the screen pops up every time it gives a verbal direction instead of just giving directions in the background (with the screen off). Its real time traffic, however, is excellent as is its common sense routing. The maps are also, in my opinion, exceptionally clean and viewable and are downloadable for offline use. I consider them to be superior to the Here Drive maps. The other program I have tried is gMaps Pro which offers some sophisticated mapping and locational options but in spite of the fact that WP says it should offer voice prompts I have never found them to work.