So far I really like this bag. There are a few things that I wish were slightly different (described below because I always appreciate detailed reviews on products), but it's exactly the bag I've been looking for to size up slightly from the smaller fanny pack I've had for years and the things I wish were different are pretty small, so I'm giving this bag 5 stars.
The bag seems to be high quality and I do think it will be protective of my kindle or phone! It took me a little bit to figure out the best organization of the bag, but I'm now able to fit everything that I want to have with me on a daily basis and I was even able to get some things in that I wasn't able to fit in the bag I was using before this. I love that it's boxy, which makes it able to fit a lot of stuff without it looking bulky. I have a 6th gen kindle paperwhite with a case on it and it fits well in the kindle pocket (though I have a lot of stuff in the first two pockets, so the bag is definitely stretched about to its limits with the kindle added). I got the 43" strap and it is plenty long enough for me (I'm 5'4" and usually wear a size medium in clothes). I really love that it comes with a small additional bag that can be clipped onto the main bag - I store both my earbuds (Samsung Galaxy buds) and my earplugs (Loops) in it and they both fit nicely. I also was pleasantly surprised that my bag shipped only a few days after I ordered, despite the pre-order countdown saying there was almost a month left before the next shipment.
Things that aren't my favorite:
1) In my first few days of wear, I've noticed that the strap makes it slightly hard to get at the zippers to open them, particularly when the strap is shortened to be more of a belt/chest bag style instead of a longer crossbody purse style.
2) The interiors of each of the pockets are all the same velvet-y fabric, which isn't my favorite feeling, but I'm overall fine with it.
3) I got the black color ("the classic") and the pocket interiors are black, which makes it difficult to see clearly into the full pocket. My sister got the tan color ("iced coffee) and I'm pretty sure that one has tan pocket interiors, so it’s probably just an issue with the black specifically.