It seems the original PoGo buddy system remains operable if we don’t enable the buddy adventure features (i.e. an occasional buddy candy is earned just by having the buddy when you walk) We aren’t being forced to use it in any significant way.
That’s a bit of a relief. Although I expect Niantic to ‘encourage’ us to use it through Special Research tasks (kind of like the way we’re forced to try AR or the friend system from time to time if we want to get the research rewards).
I’ve done yesterday the same. But there’s a strange thing I still don’t have found explanation.
If you look the second page, the one to the righy, with the summaries, there are two rare dates.
The first is “Total days”, in my summary it’s still in 0, as if I haven’t played with the buddy.
The other is the counter of km walked together with the buddy. It’s in 301 kilometers, so maybe it’s the overall counter, but then it doesn’t help to know how many hearts it has given.
I’m not concerned about getting the full 10 every day.
I might regret this later if the end rewards end up being important or significant.
Just like Smeargle, if I find it’s too much of a hinderance or time consuming away from catching and battling Gyms for Gold I won’t bother with it much and wil take what I get with little interaction.
I just wish there was a way to see how many hearts you have earned in total so far, to know exactly how close you are to the next buddy level.
You can see it, it’s a screen to the right, like changing from Pokémon-list to Raid-list.
He’s wishing there was a displayed number not a guess how much is coloured in heart.
Reached the second buddy level with my first critter today.
And pretty soon he brought me my first present… a green bag of swag containing 6 nanab berries… the opening of which revealed a new heart to collect - making the basic daily ration increase to eleven!
I have become Great Buddies with my Shiny Sandshrew, too. 
My buddy just gave me a sack of Razzberries
The next level is far away, that’s why the progress isnt visible I guess
Did 3 raids today, and on 2 of them while trying to catch monster, my buddy knocked the ball back into play and caught them.
Not quite shure what you want to tell… was it good or bad for you?
Taking a minimal interaction approach to this buddy stuff.
Feed, photo and tickle first up.
Feed again twice during the day to get the 3.
The new stop/gym and battle takes care of itself when I battle gyms.
Any k’s it registers is seen as bonus hearts. I’m not interested in pumping a ton of berries into my buddy as they are for Golding Gyms.
As time goes on it will be harder to spin a new one and I won’t be going out of my way to search for new ones.
I can’t be bothered swapping buddies in and out either.
Now I have seen doing my buddy the same… now I understand your comment. (and really don’t know why I have not understand it before, beg your pardon)
It seems I have a new problem…
No problem to take photos of my buddy (and sometimes with luck and Smeargle appears).
But today I tried to make photos of other Pokémon, and nothing, the AR screen is black and no Pokémon appear.
After this I tried to use the camera in the capture screen of a wild Pokémon (it works without AR, more as capturing the screen), but it doesn’t count for investigation (5 instant photos of Pokémon type Ice).
Problem is solved installing the new version 0.163.4