I don't see why not. I've used mine on my s2 and now my s5 no problem.
This EasyAcc Solar charger panel is Great. It charges my HTC One X fairly quickly. I mainly use it, for when i'm out & about on either of my mobility scooters. I've added a strap so it can hang around my neck. I'm very impressed & can recommend this product :-) :-)
No! I tried to recharge a Samsung S3 last summer. No reaction. I was in the open field, the sun was enough, but no response.
My girlfriends HTC Incredible S cursed. Very slow but cursed battery.
It works on a Samsung S3 and Galaxy Tablet 7". If you have the same fitting as the S3, it should work
I've also used it to charge a Huawei phone (same fitting) and a Blackberry (one of other connections you get with it.
They all charged fine.
Just look in a shop at the S3 and S4 connections. If they're the same, it'll work.
Think NO. It does not charge my Samsung S4 active, so I assume it will not charge regular S4. It charged my old S3, but when I switched to S4 Active I had to buy another solar charger.