The truth is:
A. Several types and makes of modern phones can (or might) have their innards shaken on a motorcycle. Whether this is more likely to happen on one make over another doesn’t really matter one jot. Nor does it really matter if some bod says it has never happened to them; it has happened to sufficient others - for whatever reasons - to be known and accepted as a significant potential problem.
B. Vibration induced problems not withstanding, phones and the variety of apps available can and do make very good GPS devices. That they also make very good, cameras, email handlers, note takers, egg timers, spread sheet handlers, spirit levels, TV viewers, social media hubs, diaries and even (remarkably enough) phones is just a bonus. That the phones now integrate well with modern vehicles’ screens and control surfaces is just a bonus, too. The reason why they integrate is obvious: It is because the vehicle manufacturers have made the vehicles integrate with the phones, not the other way around. In other words, the phone people won that battle. That the phones will operate on older or more basic vehicles too, is the last bonus.
C. Stand alone GPS devices and their associated and various software apps (largely used for route creation) are very good too; they have been for years. They are designed for one purpose and are now all reasonably or even very robust, certainly good enough for real off-road use. That some have morphed into infotainment systems in their own right, capable of running music, taking and making phone calls, displaying texts and more, is (in some quarters at least) a bonus, too.
D, We therefore have two competing tools for just one job, that of providing reliable GPS navigation. Here the world divides into the two camps. One favouring phones, the other a dedicated GPS device. Both camps are, depending on how you look at it, right and wrong simultaneously. In other words, there is no single truth out there. They can both exist simultaneously and in parallel to each other, both camps quite happy with their choice.
For what it’s worth, I like my iPhone, for all the things it can do. I like dedicated GPS devices too, but having for the first time owned a bike with a TPS (basic navigation display capable) screen, I thought I’d give the phone a go. A part of this decision was driven by no more than I joined the beta testing crew for the new BMW Connected app, which can only work via a phone. Inevitably, what I feared might happen, happened. My iPhone 11 Pro in its case is too fat to fit into the BMW cradle. The phone, out of its case, is quite slippery. Taking it out of the cradle with cold hands, the phone slipped fell and hit my brick drive, shattering the screen. The phone still worked but the screen stated to lose shards of what I take to be glass, which suggests to me that it would lose whatever waterproof qualities it might have possessed. The screen was now very difficult to see through, whilst the face recognition function had given up and the keyboard inputs very flakey. In short I was perhaps lucky the damage was not worse and, being in central London, I could get it mended quite quickly. That being said, had I been solely reliant on my phone as a reliable GPS device on holiday, I might well have been looking at a significant problem.
Of course I could have dropped my GPS device and had that smash. That though is definitely less slippery, more robust and having it smash, still leaves my phone (with all its devices) intact. I don’t have that fallback safety net with just a phone. As the OP is maybe now realising, that is a potential and possibly significant problem, so he’s now buying a second phone. An odd thing to admit perhaps, as he had previously been critical of people running two devices. But hey, everyone is allowed to change their mind.
