As Apple has continued to make the iPhone thinner and thinner with each passing generation, many users have voiced the opinion that they'd much rather have a thicker device with a bigger battery than a device on the verge of becoming impossibly thin. While Apple has undoubtedly increased the iPhone's battery life over time, those advancements typically accompany a new form factor that allows for a bigger battery. When Apple maintains the same form factor across generations, the leaps in battery life are more subtle. For instance, the battery life for video playback, Wi-Fi usage, audio playback, and 3G Internet usage on the iPhone 5 and iPhone 5s are exactly the same. DON'T MISS:- Oh good, another stupid theory on what’s going to kill the iPhone With the leap from the iPhone 6 to the iPhone 6s, Apple did make a number of more noticeable battery life improvements, but many users still find themselves having to juice up more frequently then they would like. With this as a backdrop, one has to wonder if people complaining about iPhone battery life is just a fact of life or if battery technology will ever advance to such an extent that complaints about battery life seem like a relic from a bygone era. Might we see a time in the near future where iPhone battery life is measured in days and not hours? Tackling this issue, Dee Strand , the Chief Scientific Office at Wildcat Discovery Technologies, recently sat down for a Reddit AMA where she asked readers to ask her anything (anything at all!) about lithium ion battery technology. Of course, it didn't take long for someone to ask a question about the iPhone. The posed question reads: "All I want to really know is when do you think my iPhone will be able to go a good 2-3 days of actually heavy daily use days before needing to be charged." Strand responded: I love this question. First of all, I am not addressing any particular cell phone company or model - all answers are general trends. The answer may be never - as the definition of "heavy daily use" means many things. With every improvement in the battery, the cell phone company wants to add more features (and so do you - consumer demand drives more features). Bigger screen, brighter display, more apps, touch screen features, etc. All those great features are designed to work such that your phone can (hopefully) last a day with recharge overnight. The batteries will continue to get better, but the phone will continue to to [sic] get even better. Your current cell phone battery can last several days if you don't use many of the features. On the other hand, if you really do have "heavy use," it would be difficult for any phone to guarantee several days of charge. It's an interesting and rather astute answer. In fact, we've already seen it play out before on previous iPhone models. Battery technology isn't stagnant, but it does move forward at a relatively measured pace. Over the years, as battery technology has improved, Apple has adorned the iPhone with more and more battery-draining features, from LTE support to the Retina Display originally introduced on the iPhone. Looking forward, it stands to reason that any leaps in battery technology may be completely offset by crazy new technologies Apple incorporates into future iPhone models. If Apple strongly believes that 10-12 hours of usage is reasonable before needing to recharge, it's a safe bet that Apple will focus more on the user experience than on-squeezing out 2-3 days worth of battery life. It's important to note that multi-day battery life isn't some far-fetched notion. Indeed, if battery life was the deciding factor in smartphone ownership, the Motorola Droid Turbo 2 would be the most popular device on the market.

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