No, stick with the iPhone and jailbreak it.

Potion wrote Stick with the iPhone 5S I had a galaxy s4 and its battery was shot after a year and it became a useless thing i had to carry a charger for. Honestly i switched to iPhone and have been happy with the switch, so i would say stick with iPhone and upgrade to the iPhone 6 later on when it comes out.

Couldn't you have just replaced the battery, or get an extended one?

Ive had iPhones since they first came out and i would probably say the S5, maybe because im bored of them, you might enjoy them though. Jailbroken iPhones are awsome.

You already have one of the nicest phones available, so I wouldn't bother switching unless you really dislike iOS. I also think that Samsung has the worst software and ugliest UI on the market, so I don't suggest their phones. You can get better hardware and software with the LG G3, HTC M8, Nexus 5, Moto X.

You do you.

If you like iPhone, then i would say wait until September and get the iPhone 6

It depends entirely on what you want from a phone. If you want a no fuss, easy working out of the box polished and well constructed phone, the iPhone is going to be a better choice. Plain and simple.

If you want raw power with better 'future proofness' (hate using that term) then the Samsung will most likely do better. As more phones are using Snapdragons over other processors, it's making it easier for app developers to make apps for mainstream phones. Apps will become more power hungry but at the same time more optimised - this will be a benefit for the Samsung and it's more powerful processor and larger quantity of RAM.

Both will be very quick now and both have a very good camera (however the S5 can shoot 4K).

What puts me off with a Samsung is high price and cheap build quality. They're making so much profit from each phone since profit isn't made from specifications really.

No phone is better than the other for everyone. One of the phones will be better suited for your needs. If you use apps like Facebook, Instagram and game casually, iOS has better performance for that. If you want the customisability, better battery life and speed that does keep up (and sometimes outperform the iPhone) then go with the S5.

Apple are due to announce the new iPhone soon, so I'd personally wait until then (early September).