Mine is 2 small for all the essentials. Went to my local halfords but not much to look at.

Its hard to judge without seeing them in the flesh. I suppose I could order 4 or 5 and keep the best one.

2 tubes, 2 co2 cartridges, levers, house keys. Possibly phone.

Would love it to be waterproof!

It won’t take a phone, but my Elite tool bottle contains:

Two tubes
Two CO2 cartidges
Lezyne mini-pump
Topeak Minitool
Latex Gloves
Spanner (I ride fixed)
Wet wipe
Small first aid kit
Sits in the second bottle cage

I also have smaller decathlon tool bottles that take one tube and most of the above.

Brilliant, never thought about one of them.