Carry a smart phone if you have one. Leave tablets or notebooks, no matter how light at home. Every gram counts, and grams DO add up quickly to become kilograms.
The only exception I make is for someone who must maintain a blog or conduct some other sort of "business" while on Camino. In this case, you make a logical choice to hump the extra kilogram or two for the device, protective case and charger/ cable, etc.
Personally, since 2015, I have used my iPhone for everything. This one device replaced a SMS flip-phone, Canon digital camera, and iPod Touch. However, I do not maintain a blog.
Also, before I leave, I set up an auto-reply message on my g-Mail server that tells anyone who is also in my Contacts directory that I am on Camino and to please NOT send me anything not urgent and requiring an immediate reply. This reduces my daily e-mail to commercial stuff. These messages do not require reading and can be easily deleted.
Over the two Caminos I have done with an iPhone, I can report that I used the phone everyday for virtually everything EXCEPT as a phone. As I have t-Mobile for a service provider, and they allow me to use my 5 gb monthly data in 140 foreign countries with no roaming fees, I can use GPS routing, mapping, translators, research, online guides, weather, and whatever else. These devices are an electronic analog for the Swiss Army knife, with everything but the kitchen sink on it.
I hope this helps.