Apple will likely unveil new iPhones next month, but analysts are looking further ahead and see a 2021 iPhone with Touch ID under the display rather than below it.

As 9to5Mac reports, TF Securities analyst Ming-Chi Kuo believes Apple is planning to bring back Touch ID in a new form come 2021. The old version required the user to place their finger over the Home button (above) in order to register an input, but there's been a move away from buttons and toward an all-screen experience, which saw fingerprint sensors replaced by Face ID on iPhones.

In-display fingerprint technology already exists, so why is Apple waiting until 2021 to use it? According to Chi, the technology isn't good enough for iPhone yet. Apple thinks the 2019 solutions consume too much power, don't offer a large enough sensing area on the display, are too thick for the iPhone's thin frame, and the yields from manufacturing are too low to be reliable for the scale of iPhone production.

2021 makes sense because Chi believes all of those problems will disappear over the next year and future generations of under-screen fingerprint sensors will satisfy Apple's demands. In particular, Chi believes Qualcomm's 3D Sonic Sensor will be the solution Apple ends up going with in its refined 2021 form.

It's worth noting the Samsung Galaxy S10 uses Qualcomm's existing 3D Sonic Sensor as an under-screen solution.

Rather than replacing Face ID, it's thought the new Touch ID will complement it. If you want a very secure iPhone, you could require both a fingerprint and your face to unlock the device, but that does seem a little over the top. I'm sure many would prefer a hidden Touch ID and no Face ID so as to remove the need for the notch. Although, if Xiaomi can put a camera under the screen, maybe Apple could do the same with the Face ID components in future.