Aside from that, I still get decent battery life out of it even in Android by carefully policing what runs on it. I have very few applications on my phone that run in the background, and I don't have the Google apps installed - I use microG instead, which is a FOSS implementation of (a subset of) Play Services.

I'm aware that the vast majority of users probably wouldn't like using their phone the way I do. That said, this should make it clear that battery life is very much affected by the software you run.

"Warning first: Never try to move the battery unless it's broken and need to replace. Because there is very very strong adhesive sticker between battery and motherboard.And too much effort or careless operation will break the motherboard."

It's also difficult to maintain the waterproof seal when reassembling the phone. So while the Z3C has great battery life, you're essentially only going to have that for a couple of years.

All other things equal, I will always pick the slightly thicker phone with a removable battery over the one that might have me breaking out the spudger.