You can carry around an external battery pack with any phone. It's not quiiiite as convenient because you have have your phone plugged in and that can sometimes be awkward to carry (but not bad if you normally carry a purse or backpack). Though it does avoid the need to power cycle your phone and my battery pack can charge my phone several times (and can charge multiple devices).
Honestly, best purchase I've ever made. It's so stressful having a phone die and the battery pack keeps that from happening.
Never had that. I used to carry a power bank on longer hikes though. Has a few pros over a replacement battery (multiple recharges, device independent, not as flimsy etc.) at the cost of being bulkier.
Well, there are some significant negatives to a powerbank solution.
Charging from a powerbank takes a long time. Swapping a battery for fully charged one can be done in half a minute.
You need to make sure the cables stay connected. How many times did you have phone on charge in a backpack for an hour, only to find out it wasn't charging because the connection got a little loose?
Each charge cycle reduces lifetime of the battery. If you have two batteries to swap between, you effectively double the overall lifetime.
And of course, when (not if) the battery dies, you can replace it at your leisure, instead of searching for a repair shop in the case of phone being glued shut. Battery is pretty much the only perishable component in your phone. If you keep your phone safe from falling or drowning, it can work just fine for decades. But the battery will need to be replaced one day, regardless of how careful you are. You also wouldn't need to pay the extra service fee if you can open the phone and put the new battery in yourself.
True, however the powerbank always was just a backup for peace of mind in unusual circumstances (long hike or similar). Its not like I'd regularly need more than a single charge a day.