I completely understand
@Bradypus's concerns.
On my first Camino I just had my old Motorola phone. On Day 2 it died. And for the first time in my travelling life, I had zero backups. All of my email contacts, phone numbers,bookings, flight info and tickets, you name it..... .
My Spanish is extremely basic and with no phone I had no translator. I was staying in a room above a bar. No English, no computer. The only email contact I can remember is my sons, however he uses it very sporadically, nor does he have notifications set up. Nor had I backed everything up to my own system, or thought to email it to myself. (A very obvious - and useful - tip I learnt here on the forum ).
I did manage to find someone to assist me and eventually restore my phone to life, but it was a very long three hours. The first thing I did was create paper backups.!
So as to what I carry on Camino:
On the 1st: my phone and my Mighty (downloads from my sons Spotify, I've got over 1000 songs on my playlists and it weighs 22 grams). Plus EU charger and the Two cables required. Phone was used for photos, videos, to write WhatsApp's and to record the day here on the forum. Oh, and once actually as a phone!
On my second: my phone, my Mighty, my GoPro with two spare batteries and a charger, a power bank, 3 cables, plus my EU charger. If I had used the power bank during the day or was worried about security because the Albergue just had a USB port for charging, I would charge via the power bank.
I did not use maps or apps of any description with the exception of WhatsApp, & Google maps on one occasion.
I would however if I was to walk a less traveled Camino.