Reddit reviews Hyperion Samsung Galaxy S4 7500mAh Extended Battery + Black TPU Cover (Compatible With ALL Samsung Galaxy SIV Carriers) [24 Month Warranty]NOW WITH NFC / Google Wallet-WORLD'S LARGEST S4 EXTENDED BATTERY-

3rd party extended battery. I have one myself for the S4 (though not exactly this model) and it works really well. Just turns your phone into a small brick that's easy to hold.

The S4 has 7500mah batteries available.

That might last more than four hours. I hope.

If you get a really big extended battery, it will last all day, but I'm talking 3-4 times the original size. I had a galaxy s4 with a [7500mAh Extended battery] (http://www.amazon.com/dp/B00BCJZYE0/ref=cm_sw_r_udp_awd_ZLTbvb1PEGWV8) and it would last a day or two.

And trust me, I use my phone a lot. I ran my nexus 5 from 100% -- 0% battery in 4 hours yesterday.

Hyperion Samsung Galaxy S4 7500mAh Extended Battery with NEW MicroP... http://www.amazon.com/dp/B00BCJZYE0/ref=cm_sw_r_udp_awd_JJcytb1CA4GT7

I just got it yesterday, so if you message me in a few days I'll let you know how it's going. The instructions say it has a "break-in period" of 4/5 days, but I can already tell the battery life is significantly increased.

I also got the honeycomb case they sell for it, and I love it. Flexible, but matte so it doesn't get stuck in your pocket or keep dirt and fingerprints.

I used to carry multiple batteries around for my phone. I'd have a spare battery charger in my truck plugged in with a spare being charged, a completely charged battery in the glove compartment, and one in my wallet. I then upgraded to a Samsung Galaxy S4, and bought an extended capacity battery and now I can go three or four days before I have to charge my phone. Much more convenient than having to swap batteries.

I got this one for my galaxy s4, which actually holds more juice than most stock laptop batteries. It made the battery last about 3 times longer but it also made it 3 times heavier. It weighs about as much as 1 cup of water (8fl oz). I think it's worth it to know that even if you're away from a charger for 2 nights you'll still have battery left, and that's without conserving. If I underclock my phone cpu, turn down screen brightness, and turn off mobile internet and only text and make calls, my phone would probably last a week. If you're looking to only use about 50% of your battery life per day, I would recommend the slightly lighter version.