But is it worth the hassle? Will a new battery really give your phone another full year of good service, or will you just be postponing the inevitable -- having to buy a new phone in a month or two?
Owners lining up for new batteries
College student Delaney Griener says her iPhone 6 won't run a full day anymore without the battery dying.
"It makes it through half the day if I use it," Griener said. "If I don't use it, it lasts a little longer, but not a whole day."
We found Griener visiting the franchised repair shopU-Break-I-Fixto try to sign up for Apple's new $29 dollar battery replacement program.
The employees at this store, and other repair shops like it, are among thousands of authorized techs who will be replacing iPhone batteries in 2018.
Manager Joe Theisler says it's well worth replacing the battery if you have a slowing older phone, especially if it doesn't hold a charge long or if it gets very hot when you're on Facebook or watching videos.
He said batteries typically start going bad after a year and a half or around 500 charges. After two years, he said, most phone batteries fail, no matter how well you treat your phone.
"A new battery will increase your battery life, make your phone last longer during the day and give you a better experience," he said.
He says a new battery will make a phone run almost as good as new (but it still won't run as fast as a new 8 or X model).
iPhone users can order a battery from Apple and make the repair themselves by watching a YouTube video, but Theisler suggests you don't try this repair yourself, unless you have opened and fixed iPhones before.
All you have to do is mix up one of the dozen tiny screws that must be removed, he said, and you can destroy your phone.
"There are lots of little screws, they all have their exact place, and they all look the same but they are not," he explained. "Put one in the wrong spot and you can damage your phone permanently."
In addition, he said it is easy to damage a ribbon connector, the lifeline that connects your phone's screen to the computer processor inside.
How to get a new battery
You can get your battery replaced if:
You own an iPhone 6 or newer (sorry, no 5s or 5Ss).
You make an appointment at an Apple store.
You visit an authorized repair shop. (Some cell phone kiosks will replace your battery, but if they are not Apple authorized, they may charge you $100 or more.)
You can also ship it to Apple, though it will take about five days, meaning you won't have your phone for about a week. Sign up through Apple's Support Page.
Griener is just thrilled she won't have to buy a new phone yet.
"A $30 battery is great," she said.
Bottom line: You really have nothing to lose by signing up for Apple's battery replacement program. Be sure to do it by December 2018, which is when the discount program ends.
If it extends your phone's life for a year, that's costing you just three bucks a month. It is well worth it, so you don't waste your money.
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