Dedicated devices are the vibe shift we need.
Is having GPS and music in a phone really the problem? I don't think it is. The problem is social media, email, and web browsing. These are the things which create distractions, and I don't think separating devices is going to solve that, unless you are getting rid of or leave behind the one device that lets you do social media, email, and web browsing...in which case, just do that and recombine the devices so that you have GPS and music and telephony.
I have done exactly as you did, but without diversifying devices. I do not bring my phone with me all the time and I do not look at social media on the phone -- but I use it for messaging with my friends when needed, which is easier for me than calling.
I have a digital camera and even a film camera, as I am an amateur photographer -- but I have to confess that in many cases the hassle involved in using those devices is not proportional to the quality of results... my iPhone does take pictures of amazing quality and allows for a huge choice of settings if one wants them.
I have several GPS devices, which I used before I had a car that connects to the phone... and I am sorry, their maps do not hold a candle to Google Maps and moreover, cost quite a bit to update and the updating itself is a complicated and not quick process.
I never play music outside except when driving and I do not find the iPod to be better than the iPhone as a player... but if I cared and it made a difference I would acquire a separate device. In my home, I have a Sonos system.
In conclusion, Andrew Wurther earlier said it better than me: the problem is not the single device, it is the social media. You can not download the social media apps or not allow them to send you notifications... it is that simple. I have done it and am perfectly happy -- if there is something on Facebook that I should see I go and see it... it happens maybe twice a month.
The problem is one of addiction: are you strong enough to avoid the temptation of the buzzing nothingness? If not, you should do whatever you need to detox, including having separate devices if that is what works.
I've also experienced in the last 5 years situations in which groups have wanted to make decisions that required having a smartphone to participate or stay safe. The attitude is that everyone has a phone; why do we still have a landline in the office or the gym? We are paying for things that are obsolete.
One for all also limits individual functions. I have been missing the kind of discussion I had been relying on for almost 30 years. It was a habit before the Web became so developed to find special interest email lists in order to have discussions with experts or dedicated amateurs on any subject that I was researching or curious about. Then suddenly, it doesn't work. I discovered that many people are now relying solely on their phones to check email. Phones do a lot of stuff but thinking while using them is still limited. Typing a two-word reply is just the easiest — or an "agree". No analysis. That's when I realized that email lists were doomed.
Thanks to my small, liberal arts college in Vermont not having cell reception, I had to watch one of my closest friends drive off a sheer cliff and then ran down a dark road knocking on every door while he literally roasted. It happened 6 hours after the last final and the school took no responsibility, and there wasn't enough time to even get one session in with a licensed psychiarist/psychologist. When the school year started afterwards, the school counselor, who wasn't licensed and wasn't a doctor and in fact had less schooling than I have now - I have a terminal degree in my field - tried to kidnap me and put me in the local asylum, on a Friday night no less, an old trick to keep someone locked up for longer than warranted, before getting let out on Monday. My school is the most digitally minimalist school you can imagine - no TV, slow internet, no cell phone reception, landlines and whiteboards on doors like a Bret Easton Ellis novel represented the ways people found each other. We had facebook - one of the earlier schools - and I've been trolling everyone from scientologists to flat earthers to 9/11 to each other on Somethingawful.com forums since I was 13. But so what if the options are available, they always were anyway. Sure, there was the implicit and sometimes explicit conceit that anything said on the internet need to be presumed as a joke until proven otherwise, and the ethos held up until our parents joined social media and didn't get the message. I happen to have a particular affinity for maps and so I both collected maps and memorized them - so GPS/Google Maps weren't too meaningful to me and I'm not really in a position to comment on whether it is meaningful or not, but I can certainly say that friction in tech contributed to a lot of trauma that I've never quite gotten over, and I was lucky - 3 out of 12 kids in that dorm, all of whom were close, graduated. I haven't been able trust a therapist since, but I get by.
Fast forward 5 years and I was working at a public defender's office and at some point, suddenly, police misconduct, something that we had long knew existed were being caught on video. To the average person whose contact with the police tends to be rare, even if you're a minority, it might not mean much, but I literally dealt with them every day, frequently in the felony context, and can honestly say that a trial without police perjury was a rarity, but impeaching their testimony without video or photos was next to impossible. The reduction of friction got innocent people out of jail on a regular enough basis that around Ferguson and Eric Garner it became a real movement. That was when I switched niches and went into immigration defense. ICE of course operates as pretend-cops and anything they do, they are never held responsible for, and being able to reach counsel and show a photo of the event that I can analyze and say "it's administrative, they have no judicial warrant, don't open the door and tell them that you're exercising your 4th Amendment right" is something that I both feared and relished, and the fear comes from the fact that ICE agents have shot and killed people with no consequence and removed even US citizens. The more data points I can. collect, the better, because it's almost impossible for the average person to conceptualize how much second class citizenship in this country that is also permanent - essentially the life of someone who entered without inspection, rides on fear, fear that is at least ameliorated temporarily by easily amalgamated tech, sometime I wish I had in college.
Hate the player, don't hate the game. The game, after all, saves lives and allows for someone who knows how to use it to remain free. ICE detention, of course, is not based on criminal charges (or they'd have judicial warrants... and free legal representation not from a nonprofit), and indefinite if they want it to be. These are not trivial matters. I understand friction sometimes being necessary, but this friction is frivolous and the consequence of the friction is way, way, way, too real.