Android

If battery's important to you, I'd recommend the S5. The HTC One may have a good battery, but it's sealed-in. Which means that any problem caused by battery issues will require you to contact HTC and spend some weeks without a phone (and cash) while you send it in for service, when you can simply exchange a battery on the S5. Take in mind that battery issues are the cause of many problems one would think are software issues (slow speed, freeze, etc). Plus, if you don't like to wait for your phone to charge, nor to be immobile while you have use your phone while it's charging, with the S5 you can buy a second battery and simply swap 'em if one of them runs out of juice.

Regarding call quality, I cannot give a fair opinion. I haven't tried ...
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