Earlier this month, U.S. hardware company Qualcomm gave a demonstration of a working fingerprint sensor integrated into a screen. While the news garnered its share of excitement among smartphone owners — the technology is rumored to be on the upcoming Apple iPhone 8 — one analyst says to press the brakes for now.

In a new report, Apple analyst Ming-Chi Kuo said the prototype from Qualcomm is still far from ready for consumers, according to 9To5Mac.

Read: Qualcomm Beats iPhone 8 To Embedded Smartphone Fingerprint Scanner

The early prototype showcased by Qualcomm at Mobile World Congress Shanghai already features strong technology that can efficiently scan and differentiate between real fingers and faked clone fingerprints. The hardware can also detect a user’s heart rate and blood flow. But as Kuo notes, the tech still has room for improvement in several areas, including scan speed and responsiveness.

In addition, Kuo points out that mass production for these sensors can be difficult thanks to the differences in screen material and thickness used on smartphones. Kuo also says that consumers aren’t necessarily opposed to having a rear or traditionally placed fingerprint scanner on their phones.

“Consumers don’t seem to have much of a problem with fingerprint scanners on the back of handsets,” Kuo writes. “Thus, handset brands may be less compelled to adopt the ultrasonic solution as long as risks persist.”

Qualcomm’s original fingerprint scanner demonstration came on a modified phone from Chinese manufacturer Vivo last week. The sensor can reportedly work through a display, glass or metal. In a release teasing the demo, Qualcomm said the technology could be seen in commercial smartphones by the first half of 2018.

For smartphones and the upcoming iPhone 8, the feature has been a persistent point of interest and speculation. As screen size has become an increasing emphasis for current-generation smartphone manufacturers, many have looked at eliminating physical fingerprint sensors in a bid to maximize available screen space on the phone.

Read: iPhone 8 Rumors: 10th Anniversary Device Will Charge Faster With 10W USB-C Connector

Fingerprint sensors are commonly used as both a home button and a way to verify a user’s identity. Some manufacturers like Google have moved the fingerprint sensor to the phone’s backside, while others have investigated technology similar to Qualcomm’s.

Apple is one company that’s reportedly doing so. The upcoming iPhone 8 has been rumored to use either a rear fingerprint scanner or an in-screen sensor, though the smartphone is widely expected to feature the latter and may use Apple’s own internally developed sensor. However, several analysts have reported on supply chain and development problems with the sensor that could keep it from being included in time for the iPhone 8’s expected fall 2017 launch.