It depends on what part of the world you live in. At minimum, for the developed world, you’ll probably need at least #3 to maintain a job and connectivity with various government and commercial entities.

I’ve done no. 1 a few times for a month or so each. Some of the biggest problems with that are:

• Banking can be a bit rough without the app. You can sometimes get a separate device to log in from some banks
• Digital authentication to eg. government services, and some private services as well works via a smarthphone app. Depends on the country a bit how extensive this is, Sweden has been really bad considering this.
• Sometimes public transit only/mostly sells tickets through an app
• Digital maps and route planners are very convenient and not having them substantially increases the time and effort you need to put into finding places

What usually won’t be a big issue

• Messaging: Whatsapp, Signal and obviously Facebook Messenger work on the computer, so you won’t be fully missing out on anything. Also, SMSs and calling work well and are cheap/free
• Missing out on social media and digital entertainment like youtube on a device that you carry 100% of the time is probably just a good thing
• Photography, you can find all kinds of digital cameras, camcorders and DSLRs for a reasonable price

All in all, it’s feasible but quite inconvenient at times.

I find having a smartphone without a sim card at home to be a good compromise. It limits the time I spend on my phone, which in itself is nice, and subsequently decreases the amount of data that can be collected of me. Also, if you aren’t relying on your phone it doesn’t need to be nice and expensive.

I didn’t have my first smartphone until my 20s.

I’d imagine it would be similar today. A purse full of maps, important phone numbers in my head, Skype on my computer to talk with my family and friends.

In the early days, I would go to the library to use the computer and Internet.

All of those are possible in Japan provided 4 allows having a landline.

That said, you’re going to end up using a smartphone anyway since the tax agency will have you do your taxes on a loaner device if you don’t have one. Several other things become more time consuming as well.

They made it impossible since last year by removing all other options for some services.
Technically I could still do without one if I drag a laptop or tablet with me and have internet.

Does the US count as a “modern-day developed country?” 'Cause if so, it’s apparently still possible because my tech-illiterate Boomer parents manage it.

(Okay, they technically have smartphones, mainly because I’m trying to drag them kicking and screaming into the 21st century, but they basically use them for nothing but phone calls and maybe an occasional text message or email. My dad accesses banking stuff via website on his computer, but if he didn’t have that I’m sure he’d just be fine going to the counter at the brick-and-mortar branch.)

I’m kind of living the 1) life, I have a degoogled smartphone in eternal airplane mode and only free software apps. So in practice I have none of the apps “required” to live.

In large cities, transportation is getting more and more difficult without uber. Bike/escooter rentals also stopped working without an app. I use osmand on my offline smartphone to find taxi stands, so that’s cheating by your standards, but stands are empty these days and the drivers are a bit surprised and comment that “most people order a taxi by phone these days”.

I’ve lost most of my friends when I quit facebook, when we randomly meet we still have a small chat but I don’t get invited to events (birthdays etc) any more. Big respect to the few that still don’t mind sending an sms or email (and even more respect to the 2 friends who keep an xmpp client with only me as a contact)

Increasingly, I don’t know what’s going on around me because businesses, libraries etc advertise only on “spotted” on facebook, have presence only on fb, and don’t even care about telling the local news about events or openings. I only know about that because of other people who use facebook.

1 & 2 are no problem at all, I did that (2) till a couple of years ago.

I live in Germany. For the moment, i do not require a phone for anything in my life. I use it as an nfc card reader for my ID, but there are usb readers that could replace that. All other things also would continue working without a phone. Email, matrix, osm, music all work on a laptop or raspberrypi.

A friend of mine avoids smartphones as he is (rightfully) very concerned with his privacy when it comes to big tech. So he has a PC and a dumbphone.

Doesn’t difficult very much depend on what you think matters? You’re instantly missing out on anything app, anything QR-code related (ordering food in some restaurants, links, etc.), membership cards that no longer exist in physical form. Some places sell certain tickets online only and then you may need a printer or you’re SOL. I’m sure in missing something so that’s not extensive.

But at the same time, if you have a dumb phone, you can still stay in touch with friends and family. You’ll be missing out on images being sent that are bigger than 2 pixels. But you wouldn’t be completely out of the loop. And if you have an internet ready computer at home or at the next door library, just not on you at all times, I think that’s crucial. Without that you’re ending up in all sorts of trouble.

I would say it’s doable if you are good at not giving F’s. If at the same time you only want to use cash or just no credit cards you’ll be making your life much harder though.

I did these in China.

4 first, poor had nothing, moved to teach English. It was fine, I paid for things with cash, I had a debit card to use the ATMs.

And up until that point I still didn’t have any phone, so I climbed the hills behind the apartment I was renting and just walked around town learning stuff, trying for, living life.

Then I got a dumphone, which changed little except I could hang out with close friends from the school but usually we coordinated when we work together in the school anyway, so there was very little change with a dumb phone.

Then I bought a laptop and I could study Rosetta Stone and watch TV/movies.

eventually I got a smartphone and then I could start dating in the modern world. I dated in China before that through organic meetups, but I didn’t realize how far into the digital age dating head lapped until I got a smartphone and used all the apps.

It’s very feasible and I’ll say a lot less stressful to not have a phone, but it’s not as anxious-fun, and I do like looking stuff up all the time and having gigabytes of music in my pocket.

which reminds me before I had a laptop or smartphone, I bought a mini iPod in China and used one of the school computers to load it up with music.

Shoot that was a revolution for me, I loved the little clip on the back and how late it was.

How bad would it be for your social life?

I’d say that without the tech you won’t make new connections as easily on a surface level, but whenever an unteched person does get into a conversation, their side of the conversation tends to be a bit more well thought out and significant.

You’ll also put more work into the real life relationship since you don’t have a hundred virtual relationships vying for your attention on your phone.

So it would probably help your social life, by my metrics.

In your four scenarios.

1 is doable the rest are not.

You need a voiceline/phone.

I guess you could use a soft phone.

In the US, it’s not a requirement. I use my phone for nothing but occasionally making or receiving calls, taking photos, and messaging friends, but all of that could be done without it. I just use it because I have it.

Kids and elderly people are already doing all of that, so it is technically possible, but inconvenient. You would also need to outsource your smartphone activities to someone else to actually make it work.

Option 1 seems semi-feasible, but it is getting harder every year. Also, certain activities are already beyond your reach if you’re in this group. As long as you don’t want to do any of those things, you should be fine though.

Option 2 is impossible unless you outsource your phone needs to someone else.

Option 3 is hard, but possible. You would need to limit your activities quite significantly. BTW some homeless people have a dumb phone as their only electronic device. You kinda need to have a phone number in order to barely survive.

Option 4 is the most extreme one. Children and elderly are living like this, but they are also outsourcing everything, so does that count?