I try to get out of the rabbit hole of carrying stuff. But lately, I have really seen the value of compact daypacks, especially for shopping or just dumping a hoodie and a water bottle etc.
I also feel that there is a point where they are just too bulky real quick.
The one that gets the most use is this one.
Got it for AU$6 delivered, and it packs down real small.
The caveat is the inside seams were all single stitch, which would probably hold up for longer than most would estimate. Owning a mini overlocker (serger) i just reinforced all the seams in a few minutes. A patient person could run a zig-zag, or a straight stitch with bias binding with a regular sewing machine.
There are some other similar generic models like this one with cosmetic variation that are slighlty dearer. Some even have pictures of the inside that appear to have bias binding.
The main thing i say is the small pouch, big single zip opening and the adjustable mesh straps. I carry mine clipped to a 410ml or 600ml waterbottle, sometimes just to my belt loop. Summit to Sea Ultrasil Daypack is a similar size .
The second style i have is two that are clones of the Matador Daylite 16
One is the same brand as the previously mentioned backpack. It has proper biased bound seams but is bulkier.
The second is badged as 'Lost' foldable backpack and was sold through the COTTON:ON clothing chain here in Australia. It actually has manufacturer labels and is a slightly higher build quality.
Packed down in the pouch they are 30-40% than the other design and i don't feel it's worth the added bulk for the few extra features.
The last one I currently have is a Ripcurl Packable Daypack. Paid AU$10 for New Old Stock.
Unpacked it is a very good simple design and will probably hold up to much more casual abuse. However, packed it is just too bulky to carry without another bag.
Things like checked luggage or if you take a large single carry on and want something smaller for day trips at your destination.
If you are doing this it is probably best to pack it by laying it flat open rather than scrunched it into its own pocket pouch.
All in all how small it packs in its pouch/pocket affects whether I bother to take the foldable bag. When i do take one though i am always impressed at how handy they are over a shopping bag or o stuff clothes/ items in when the weather changes.
So much so I have an Summit to Sea Nano Daypack in the mail. Its 30g and the size of an egg so hoping it will live on the keychain. The straps are concerning but i may mod them if the rest of the bag holds up.
https://www.lacrux.com/en/klettern/the-lightest-backpack-in-the-world-ultra-sil-nano-daypack-from-sea-to-summit/Will put up shots of my own units side by side . So what have you got , what do you use it for and what is your philosophy on size and functio?.