Lessons learned after changing the battery a second time in my old iPhone 6s...

1. Despite what you see in the YouTube video, expect it to take more than 3 minutes, probably much more.

2. The tools that come with the battery are useless in getting the screen to separate from the phone base. Being very careful, the edge of a small knife blade will get it started to the point where the plastic tool can be used to fully separate the two.

3. The worst step by far is getting the battery to separate from the base. The adhesive that is supposed to release when stretched doesn't always work as designed. Some prying will likely be necessary so be careful. A twisting motion once you get the edge of the plastic tool under the edge of the battery seems to work best, working slow and you work towards the rear of the battery.

4. There are ribbon cables that connect the electronics in the base to the screen. As the videos show, you don't want to bend these to far by bending the screen back more than 90 degrees when replacing the battery. One video shows disconnecting these cables, which might be best but requires more work. I was able to change my battery twice by just being careful with the screen.

5. The ribbon connector on the battery is easy to remove with the plastic tool, but getting the connector on the new battery properly seated can be a challenge, especially if the ribbon is a little out of shape. Before removing the old battery, notice how this short cable folds neatly between the battery and side of the battery compartment. This fold ensures the connector is in the proper position to plug into the connector. And don't forget to replace the cover for this connection. It's an absolute must to keep the connector in place. No need to ask me how I know.

6. When replacing the screen, begin by inserting the tabs at the top of the screen first or otherwise you'll never get the top to press into the phone base.

IMHO, if you can break down and clean your own firearm, you have what it takes to replace the battery in your iPhone.

I agree this isn't a hard job. One piece of advice is to make sure you don't puncture the battery. It will, I repeat it will catch fire if you do.

^^^^

This was my experience exactly when replacing the battery in the same phone.

I will clean my own firearm.

I will spend the $90 to have an iPhone battery replaced.