Technology Blog

First Apple Watch with cellular will benefit from a strong mobile signal




The release of the new Apple Watch Series 3 is making noise in the marketplace because it’s the first Apple Watch with built-in cellular connectivity. Apple promises Series 3 users the ability to “stay connected when you’re away from your phone.”

In practical terms, this means that Series 3 users can make calls, send texts, stream music, and more, entirely with their watch. Previous versions of the Apple Watch required an iPhone in close proximity for all wireless connectivity. The LTE version of the Apple Watch Series 3, however, allows users to switch to mobile carrier networks for wireless connectivity for usage when it’s not convenient to carry an iPhone.

A cellular smartwatch has a much smaller single antenna than that of a smartphone, and as a result will be less sensitive to weaker signals than larger mobile devices with antenna diversity. Apple has placed the antenna underneath the watch display, demonstrating tremendous innovation in keeping the slim form factor of Apple Watch. Existing cellular smartwatches such as Samsung Gear and LG devices rely on added volume to accommodate LTE antennas or embed them into the bands of the watch. Additionally, the Apple Watch Series 3 Cellular supports a smaller selection of mobile network bands, or frequencies, than modern smartphones.

The impact of these differences is that not all networks are created equal and not all Series 3 Cellular users will experience the same level of connectivity. Especially, at the cell edge, Apple Watch could encounter difficulty holding on to weak LTE signals, presenting a sub-par mobile performance relative to that of the companion iPhone.

Connectivity will differ, depending on carrier and location

While the Apple Watch Series 3 promises many benefits (particularly for those who want to stay connected while exercising), the ability to connect and the quality of connectivity will vary, depending on the mobile network associated with the watch, as well as a carrier’s performance in a particular location. In order to utilize the connectivity features of the Series 3, users must pay an additional fee to their mobile network, and the carrier must be the same as that of the user’s iPhone.

In situations where a user’s iPhone is not in close proximity to the watch, not all US carriers will deliver the same level of connectivity. With AT&T or T-Mobile, the Apple Watch Series 3 uses either LTE or 3G for connectivity. However, the Series 3 does not support the 3G technology of either Sprint or Verizon. Instead, the watch will only connect to LTE to make Voice over LTE (VoLTE) calls or send texts with Sprint or Verizon.

Within major metropolitan areas, this difference in connectivity among carriers might not make a noticeable difference. RootMetrics, an IHS Markit company, has measured mobile network performance under real-world conditions for many years and has collected hundreds of millions of test samples across the 125 most populated metropolitan markets in the US, within each of the 50 states, and more. In the first half of 2017, RootMetrics assessed the network technology capabilities of the four major US carriers during testing in metropolitan markets and across the 50 states. RootMetrics testing shows that all four carriers offer a strong LTE footprint within the 125 largest US metro areas.

Outside of metro areas, however, users could see different performance, with coverage gaps particularly important to users in rural areas. This is where provisioning for the Series 3 to access both 3G and LTE networks becomes more noticeable. AT&T users will be able to take advantage of both 3G and LTE networks with the Series 3 watch, and AT&T’s coverage in rural areas outside of metropolitan markets is over 90% on 3G and LTE combined. Verizon users won’t be able to access 3G, but Verizon’s LTE footprint is robust and covers over 90% of the rural and non-metro areas RootMetrics has tested.

The story shifts, however, when considering the potential impact on Sprint and T-Mobile. The LTE footprints of Sprint and T-Mobile aren’t as large as those of AT&T or Verizon outside of metropolitan markets. RootMetrics testing suggests that across the more rural areas outside of metros, both T-Mobile’s and Sprint’s LTE footprints are at around 67%. Since 3G support is not available for the Series 3 on Sprint’s network, this means there could be locations outside of metro areas where coverage becomes problematic for owners of the Series 3. T-Mobile users, on the other hand, will be able to take advantage of 3G service when LTE is not available. For T-Mobile users, LTE coverage plus 3G coverage (much of which is provided by an agreement with AT&T in rural areas) provides a footprint close to 82%.

The above scenarios will not affect the vast majority of Series 3 users, who are likely to either have their iPhone nearby and/or will be using their watch within metropolitan areas. And, for both Sprint and T-Mobile, any performance hiccups due to coverage should ease as their LTE footprints continue to expand into rural areas.

Keep in mind that RootMetrics testing figures are averages based on millions of test samples collected across the 125 most populous US metropolitan markets and throughout each of the 50 states. That said, those figures offer directional guidance for each network’s LTE capabilities. Real-world Apple Watch Series 3 cellular results will vary, depending on how good—or poor—each network’s service is in any given location, as well as on the real-world performance of Apple’s innovative embedded display antenna design.

With the growing number of devices connecting to mobile networks as more and more objects become smart, connected, and a part of the Internet of Things, the quality of mobile network coverage becomes even more important. The proliferation of connected devices, including IoT devices like smartwatches, smart meters, eReaders, and more, require strong network connectivity in order to ensure a good consumer experience.

To learn how the carriers performed in specific US metro areas, within each of the 50 states, or across the US as a whole, view the RootMetrics series of RootScore Reports, which characterize network performance under real-world mobile usage conditions.

IHS Technology at IHS Markit
Posted 27 September 2017