> If you stood on the street corner and asked every passerby what they would change about their phone, I think you would be there all day before someone said "I wish I could replace the battery".

Are you sure about this? I've heard this complaint from a lot of non-tech people who are old enough to remember flip phones with replaceable batteries. It might be age related.

My old flip “feature phone” could go about two weeks on a charge. I miss that.