Decathlon bike backpack query.

I don't own the rucksack but I doubt a smartphone with a 6 inch screen would fit in the belt pocket with the waist belt closed around the curvature of your body.
A small emergency 3310 sizes phone would fit.

Not sure about that one but the 7l one looks more promising and actually has a phone in one of the pockets in the pictures. Cheaper too.

Just tried both so see if a Google Pixel 6 would fit. Absolutely no chance in the bigger pack, the smaller one would be incredibly tight, but with some persuasion it would fit, but won't be easy to remove.

Thanks, that's answered that question. Stupid oversight in these days of giant phones.
The search continues.

Oversight in these days of stupid giant phones.

FTFY 😉