Yesterday, my brother decided to change the battery on his iPhone X and iPad Pro that would enable him to continue to use his iOS devices for another 2-3 years. I had debated advising him whether it was time to upgrade his devices. But for his current situation and needs, I think spending nearly $200 on was the the choice. Whether that is the right choice depends on your needs and the timing of upgrades from Apple.
The iPhone X was released in 2017 and his iPad Pro in 2016. Going into 2021, it would be about 4-5 years and he'll be keeping these devices for at least another two years. For today's mobile needs and annual releases from tech companies, this is eons ago. However, Apple really build these devices to last whether it intended it to last this long. Both of his devices still run the latest iOS and has no discernible performance issues that he could tell. The only shortcoming is that his iPad Pro storage could not be upgraded.
Paying $200 at a local shop might be a bit high. At any other time, he would have taken it to an Apple store but we live in times of a potentially deadly and unpredictable pandemic so there was not a lot of options and Apple stores were all closed. Why did he decide to upgrade the battery now? The health of his battery was down to around 80% and losing that extra 2-3 hours changed his mobile activity to a certain extent. Put it another way, adding back 2-3 hours is a relief and it did made his iPhone X feel like a new device.
As for his iPad Pro, his children use it from time to time for viewing videos, doing school work, and playing games. He is also using it for his personal work as well. I had suggested that he get them another iPad back during the Holidays when various retailers had iPads on sale. I did not push too hard on it.
As for you or me, it really depends on our mobile needs whether upgrading the battery or getting whole new devices make sense. As someone who is learning to code, blogging, and possibly podcasting in the future, the current lineup of iOS devices works but there are hoops I would have to jump through and going with a MacBook would make more sense. Right now, the iPad Pro, regardless of which version, simply is not as versatile as a Mac. Perhaps, future iOS will gain some OS X features and apps like Xcode that will allow coders and content producers to run apps that have feature parity as Mac apps. I know there are video producers looking (hoping) for Apple's Final Cut to finally run on an iPad.
But if the Mac is not necessary for your needs, the iPad or iPad Pro is the way to go. And if you already have one, albeit an older one with the battery running down, that is working for you, replacing the aging battery that would allow you to go another 2-3 years is like more cost effective. For a low end iPad Pro like what my brother has, the cost of the battery ran about 10% of a brand new iPad Pro. For the next few years, it does not look like he needs any features on the new iPad Pro, like the new LiDAR Scanner, for his mobile and computing needs. So it might make sense for him to go this route.
Timing is also an issue. If you are waiting for the next new iPad Pro, there is no telling when Apple will release a new one. Perhaps it is this spring. And even if Apple would like to release it in February or March, circumstances can happen (again, we live in uncertain and uncharted times with the Covid virus) that could delay it. If the battery life on your iPad is not long enough for you to limp through for the next few months, perhaps, upgrading the battery will allow you to work through until the upgrade is released. And if you're using for work, perhaps you can expensive it.
Personally, I cannot get enough battery life. I have the new iPhone 12 mini and I am less inclined to upgrade my iPhone as much as I did before. I really like the mini despite it having less battery life than the rest of the bigger iPhone 12 lineup. So, once the battery drops to about 85% in a year or so, I'm changing out the battery if I am still using it and decide against the iPhone 13 mini. My iPad mini is a couple of years old now. The battery life suffice but I am waiting to see when the next iPad mini will be released and what new features it will have. If I'm not impressed or find that it has no added value to my mobile needs, I will weigh the cost of a new battery against the new mini.
For the most part, if your iPhone or iPad meets your needs and you're satisfied with it, then it would be more economical to swap out the old battery for a new one. If you decide your iOS device is dated, slow, and crave the new features on the newer iOS devices, then your choice is clear. Of course, it also depends on your pocketbook as well.