Tech Insight : Mobile Calls Better Than Ever

A recent ‘Mobile Phone Trends’ report has highlighted how the quality and reliability of mobile phone calls in the UK are improving. So, what’s helping to bring about this change and why is it so important now?

The Figures 

Some of the key figures highlighted in the report (by testing company RootMetrics) that show an improvement in mobile phone call quality include:

– Only 1per cent of calls dropping during UK-wide testing in 2H 2021. RootMetrics hails this as an excellent result when compared to its 2 per cent benchmark.

– Dropped calls are rare, especially in major cities (well below 1 per cent).

– Blocked call rates fell from over 4 per cent in 2017 to 1.7 per cent in 2021

– Call setup times (the time it takes to establish a virtual circuit across a telecoms network) have improved from 4.9 seconds in 2017 to 2.2 seconds in 2021.

Why The Improvements? 

Some of the main reasons for the improvement in mobile phone calls in recent years include:

– Most UK mobile phone calls (85 per cent) are now transmitted using the more reliable VoLTE. Launched by all four major UK mobile operators in 2015, VoLTE is a kind of VoIP that uses 4G LTE technology to transmit calls over the data network instead of using the older, less reliable circuit-switched connections. As well a clearer calls and fewer blocked and dropped calls, VoLTE enables the transition from Wi-Fi to 4G LTE during calls, plus the simultaneous usage of the internet while making a phone call. VoLTE also uses a Quality of Service (QoS) strategy to improve its calls.

– The use of fibre networks for digital voice services rather than networks of physical lines producing higher quality voice calls, lower volumes of scam calls, and lowering cost, complexity, and energy consumption.

– The introduction of 4G and now 5G.

– Wider, improved networks and a shift to small-cell networks (dense networks of small, high-capacity cells).

– Improved analytics for mobile operators, helping to channel investment for greatest value.

– Software improvements for operators, e.g. software-defined networking (SDN) and network-functions virtualisation (NFV).

– Improvements to smart phones.


There are still, of course, challenges to overcome to keep mobile phone call reliability levels going in the right direction. These include, for example:

– Power outages in some areas stopping IP phones from making calls, e.g. to the emergency services. However, all mobile operators claim to give the highest priority to emergency service calls, and modern smartphones now roam to the operator with the best coverage to make emergency calls.

– Coverage challenges.

Why So Important? 

The reliability of mobile phones is particularly important now because :

– Most of us use mobile phones for more aspects of work life and there is now a greater reliance on apps, e.g. WhatsApp, and collaborative working and group comms platforms, e.g. Zoom, and Slack.

– The big analogue switch-off in 2025, replacing the public switched telephone network (PSTN) with a digital, Voice over Internet Protocol (VoIP) network will make us more reliant than ever on our mobile phones for calls. Levels of quality and reliability, therefore, will need to be high.

What Does This Mean For Your Business? 

The big analogue switch-off is only 3 years down the line and most people are already hugely reliant on mobile phones for many aspects of work, social interaction via social media, plus many useful apps. Voice calls, however, remain a particularly important primary function of mobile phones and improvements such as operators using VoLTE have helped improve the quality and reliability of mobile phone calls in recent years. Coverage challenges in some more remote areas is still an issue but as the RootMetrics report showed, reliability, which is highly valued by mobile phone users, is better than ever.