I've got an S6 Active.
Not sure how that compares with yours but it gives you a size reference if you know anybody with one.
If you get the spider looking ram mount it will hold through just about anything.

 

FWIW, when I was going through the same type of thing, I decided not to add an accessory outlet.

Instead I bought a Mophie case for my iPhone 6. It increases the battery capacity by 150%

That gives me so much battery life that I never have a problem.

 

That's another great idea buddy, do you mount it on the bike for gps??

 

The mophie that has the battery is a phone case that makes your phone a little bit thicker.

I don't mount my phone because I don't want to be distracted. Instead I keep it in my pocket. When I stop for gas or whatever, I check my position on GPS and look to see what is the next set of turns etc I need to make. In other words, I use it more like we used to use paper maps years ago.

It could be mounted using a universal clamp type mount though.

http://www.mophie.com/

I paid around $130 or so about a year ago. That's a lot for a phone case but since it is also a battery that is part of the case, it is more justified compared to just being an expensive case.

 

Another option is this

http://themicrostart.com/

It essentially is a lithium ion battery pack. It has ports you can charge electronic devices with. You can also use it to jump start your bike. The larger one is even powerful enough to jump start a 7.3L Diesel engine. They also sell accessories for it such as a small portable air compressor that can be powered by it which could come in handy if you have a flat tire on your bike.

All you need to do is charge it up at your house or hotel or whatever and it has enough capacity for a lot of usage and will hold a charge for a long time.

I have not purchased this product but it is on my wants list.

So, there are a lot of different ways to go about this.

 

H4 new Led bulbs are great!I bought one with built in cooling fan for $12 on bangood.com my headlight hi/lo is much brighter.than my halogen. Also bought led brake light bulb.bayonet type socket.$10 they both use much less power.