This is how my power bank iPhone 7 case looks after one year.
Couldn't expect much from cheap one, but charging still works as year ago, and I dropped my phone on the floor many times and it's still in one piece so I can tell phone is well protected in this case.
Having extra battery capacity is a great option, but make sure you pick slim case so your phone not looks like a brick.
Cable headphones are not working with this power bank case, so you have to get wireless one.
There are many phone grips, this is very useful way to pimp your phone. You just stick it to the back of your phone case.
Why iPhone?
iPhone was always too expensive in my opinion, but I had LG G4 before and it broke two weeks after one year warranty. For this iPhone i have 3 year warranty and I havent got any problems with it so far.
Moreover LG used to freeze from time to time, iPhone never froze since I bought it.
Links, video and more on my blog:
https://alanstefankiewicz.github.io/blog/how-to-increase-durability-and-battery-life-of-your-smartphone.html