So, I currently have an S4 and have been a loyal Samsung Galaxy customer since the very first model came out. It's never disappointed me so far, but I'm wondering if I should upgrade to the S5 or the more expensive S6?
If you like the features of the S5 then yes, it has a better camera and looks a lot nicer. If you don't use or are not interested in a better camera ect then stay with the S4. For me the S5 looks a lot nicer and I personally feel the battery life on the S5 is much much better.
I'd say it isn't really worth it. Depends on how you use your phone of course, but the S6 is a kind of a big jump in mobile phone technology, and the upgrade of the S5 over the S4 is just some improvements on the hardware and software. With the S6 on the other hand you get new stuff like super fast charging - you could charge your phone in 30 minutes! That is of course to be used sparingly because I'm sure it puts strain on the battery, but nevertheless is a cool function.
As far as I'm concerned, the S5 and S6 are worth upgrades over the S4. You'll go for the older S5 if you're looking to get an upgraded device at a lower price. The S6 is the upgrade you choose if you want cutting edge technology and a more premium design. I'd get away from the S4, though, because it's starting to show its age with lackluster hardware by today's standards.
I think its worth the upgrade, especially if you use your phone a lot. I have the S5, but my daughter has an S4 and she will continually complain about the 4, however it could be that she wants a new a phone too. I can see some differences tho, the S5 is bigger and better quality in the camera, unless that doesn't matter to much. I use my phone as a camera all the time, its one less then to lose when traveling around in my opinion. My phone seems alot faster the the S4 to, but again its all about what you do on your phone and what you use it for on a daily basis.
Hmm... that's a question every phone user asks themselves once they've become attached to a brand. I upgraded from a Galaxy S3 to a S5 and I can honestly say that it wasn't worth it. My phone broke around September and the new S5 was coming out at the time. I made a tactical decision to wait 6-7 agonizing months for it because of all its new features. Once I got the phone I was disappointed. Don't get me wrong, it did everything they said it would do but it wasn't as big of an upgrade from the S3 that I thought it would be. I haven't seen nor do I know anyone who owns a S4 but if it's similar to the S3 then it probably isn't worth the update unless you fully utilize the water-proof function and the improved camera (i.e. scuba diving and photography). The best thing about it for me is that it makes a nice shower radio.
I haven't kept up with the S6 so I don't know the system specs for it, but unless it's dramatically better, I would suggest waiting until your phone broke. If I didn't have Sprint as my service provider, I would go for a Nokia Lumnia. I find myself not using the Google App Store very much and would be fine with just having a great camera at my fingertips.