I have a place in my heart for personal navigation devices (PNDs). In years past, they got me where I was going, even if they sometimes steered me onto a circuitous path. And weirdly, I miss having a Garmin tell me it\u2019s \u201crecalculating\u201d when I take a wrong turn.\nBut in the age of Waze, does anyone still need a PND? My conclusion: In most cases, probably not. Unless you\u2019re into dash cams.\nConsider Garmin\u2019s DriveAssist 51 ($300), introduced at CES 2017. It\u2019s as good an example as any of what PND makers are up to these days, in hopes of remaining relevant. I\u2019ve tested a DriveAssist 51 on and off for the past month. And while it did a reasonably good job of getting me from points A to B, there\u2019s primarily one killer feature that elevates it above smartphone navigation apps: A built-in dash cam.\nContinually recording video footage\nDriveAssist 51 continuously records video footage as you drive. If there\u2019s an impact (detected by DriveAssist 51\u2019s accelerometer), the most recent footage is automatically saved to the included microSD card\u2014which might help you financially after an accident.\u00a0Consider this Reddit post from a Houston driver, writing about a \u201ccheap dash cam\u201d he uses:\n\u201cThe dash cam sure came in handy when I got sideswiped on (a local highway) a year and a half ago. Their insurance was all blah blah blah until I said \u2018Oh yeah I have dash cam footage, here it is on YouTube.\u2019 Got a check a week later.\u201d\nSpeaking of YouTube, Garmin\u2019s free VIRB app enables you to post your dash camera footage to YouTube, Facebook or other sites.\nCollisions aside, the dash cam can be handy in other scenarios. As you reach your destination, for instance, Garmin\u2019s Real Vision feature switches from navigation to camera view, with a bright red arrow pointing to the address you\u2019re looking for. It\u2019s a touch of augmented reality that serves a useful purpose.\nThe camera also works with the PND's mapping, traffic and other data to provide alerts. When you're stopped in traffic, and cars ahead of you start to move, you may receive a 'Go' alert. (In other words: Stop checking your damn email and drive.) Forward Collision warnings alert you if you're riding someone's bumper.\u00a0\nOne other thing worth mentioning: You can pair the DriveAssist 51 with an optional Garmin BC 30 Wireless Backup Camera ($170; professional installation is recommended).\u00a0\nIn my opinion, a PND with a built-in dash cam, like Garmin's DriveAssist 51, makes much more sense as a purchase than a PND without a dash cam.\u00a0\nWill you be more vulnerable to car break-ins? \nBut there are a few things to consider.\nTo take advantage of the dash cam feature, you\u2019ll need to insert the Garmin in its included dashboard mount, so its camera (on the PND's backside) can record the road ahead. But will the presence of a dashboard mount increase your chances of a car break-in, even if no GPS is evident to would-be thieves? In some cities, like San Francisco \u2014 where car break-ins increased 31 percent from 2014 to 2016 \u2014 the answer might be \u201cyes.\u201d (A few years ago, my car was broken into in San Francisco, likely because I\u2019d accidentally left iPhone earbuds visible.)\nSomething else to consider: You can create a DIY dash cam using an old smartphone and an app. How-To Geek spells out the steps. But Garmin\u2019s DriveAssist 51 is a much more elegant alternative.\nPacked with features\nAside from the dash cam, Garmin\u2019s DriveAssist 51 is loaded with other features:\n\nVoice commands. By using the wake words \u201cVoice Command,\u201d you can navigate to addresses, points of interest, \u2018go home,\u2019 or manually save dash cam video. You can also find nearby parking (via Parkopedia), adjust the volume or brightness, and more. Siri it ain\u2019t, but it\u2019s a convenient feature nonetheless.\nFree real-time traffic. The PND depends upon Garmin\u2019s free Smartphone Link app for this information, streamed via Bluetooth from your smartphone. Of course, smartphone apps such as Google Maps, Waze and Apple Maps incorporate traffic data into routing as well.\n\n Garmin\n\nParking options. When connected via Bluetooth to Garmin\u2019s Smartphone Link app, the DriveAssist 51 will help you find nearby parking at your destination, along with rates. Waze helps you find nearby parking, too, before you start your drive or as you reach the destination.\n\nNegating the downsides of PNDs\nGarmin has worked hard to mitigate the pain points of PND ownership. DriveAssist 51 features built-in Wi-Fi, for instance, so you don\u2019t have to connect the device to a computer to receive map updates, as in the past.\nDriveAssist 51 does its best to compete with the likes of Waze, too, including red light and speed camera alerts. Plus, it tops Waze with alerts that occur when entering school zones or when you\u2019ve been driving for several hours (\u2018fatigue alerts\u2019).\nAnd Garmin has made owning a DriveAssist 51 attractive to Garmin smartwatch owners. When the two devices are paired, you can continue navigation on foot after parking your car; get driver alerts on your watch; and receive directions to your parked car when it\u2019s time to leave.\nToo late to turn the tide?\nGarmin has made a lot of smart decisions in hopes of keeping the PND category alive. But like low-cost, point-and-shoot digital cameras, it\u2019s too late to turn the tide. Garmin's 2016 fourth-quarter results showed double-digit revenue growth in its fitness, outdoor, marine and aviation units. But its automotive unit (including PNDs like DriveAssist 51) saw double-digit declines, according to The Wall Street Journal.\nYounger drivers aren\u2019t used to paying for a GPS device. Why bother, with all the free smartphone apps? At the same time, many drivers, including me, don\u2019t want yet another device to take on a trip.\nNot even the vast majority of Lyft and Uber drivers I've ridden with in San Francisco use PNDs. As a passenger,\u00a0I always note which GPS app or device the driver is using, and Waze is the hands-down favorite. In all my rides over the past year (at least 30, by my count), I\u2019ve only seen one driver use a PND (a Garmin). The driver had owned the device for several years and wanted to keep his phone free for calls, he says \u2014 which is, for some, reason enough to own a PND.\nI\u2019ve noticed that some Lyft and Uber drivers have a dedicated dash cam. Also, when ride-share drivers navigate with a device that isn\u2019t a smartphone, it\u2019s nearly always a tablet, either an iPad mini or a small Android slate. That makes sense: Why spend money on a PND when you can purchase a tablet with built-in GPS that has a bigger screen and can do a lot more?\nUltimately, here\u2019s my take: If you\u2019re a ride-share driver or frequently drive a lot; you\u2019d like the peace of mind of having a dash cam and don\u2019t already own one; and you\u2019d like to have your smartphone free for calls or music, then yes, DriveAssist 51 could be worth $300 to you. Otherwise, Waze or Google Maps is likely all you need.